The final chapter in our continuing Luger series is today’s book, The Parabellum is Back! While Sturgess’ three-volume encyclopedia covers the pistol through 1918 and Simson Lugers takes us through Weimar, that leaves a lot […]
I’d like to take a moment to thank everyone who has become a part of the community we’re building here at Forgotten Weapons. We have some folks with access to great photos and documents who […]
This is Lot 2051 in the upcoming October 2019 Morphys Extraordinary auction. The MP40/I was an experimental modification of the MP-40 submachine gun developed by the Erma company (we think) in late 1942. It was […]
Great photo! The Parabellum was a very interesting branch of the Maxim tree. I am still looking for a lock to go with my feed lock should anyone have one for sale or trade!
Joe
Fantastic, this had been my area of interest for ‘decades’ – well mostly in past. The Parabellum gun had been used almost exclusively by observes, as I recall. The one shown with drum feed looks formidable; I would not want to argue with its operator.
Here is little reading on the subject and answer why it was used primarily by observers – it was hard to make it work as synchronised. http://www.wwiaviation.com/german_guns.html
Not at hand at the moment P.doughboy, but you can probably find plenty of info on net. I think of it as one of most intriguing and in fact it is to my surprise, it did not get into wider use. It came probably little too late into the game.
I have found something’s about it off the internet.
Chinn, I presume that’s a book Kevin I’ll have a look for that cheers.
I was briefly pondering the notion that two Winchesters on a staggered mounting operating two sort of slide fire stocks which act independently of one another, in conjunction with a rotating cam/stud arrangement placed between the two which would operate the actions separately “said contraption would perhaps partially resemble a reel off a fishing rod” with protruding rods depressing either trigger at the appropriate point of each rifles cycle after initially starting off the process manually, might reactivate the concept in the U.S for novelty purposes.
I like WW1 planes, something attractive about there apparent simplicity. Wouldn’t fancy flying in one firing machine guns at one another though particularly, he he.
You might be interested to hear, PD that my fancy in flying things was caught be cheap war time sequel named Bigless – Captain of Camel Fighters. It was in translation of course and it originated from time shortly before WWII.
Soon after that I was able to read similar, but more personal account from Ernst Udet, the German Ace, in form of his memoirs called “My life of pilot”. That was starting point for me.
I got a game for my mobile phone, Rise of glory you’d like that WWI fighter plane game it’s good he he.
Well the link worked so I will briefly explain my drawing, the idea is for a mount to be constructed which would hold two 45/70 Lever action rifles while allowing them to be detached from it again easily.
The guns are mounted left and right of each other on their own discs, a lug on the forward weapons barrel mount catches the lug on the rear weapons one when it fires…
Pushing the gun back, to fire initially you load both guns pull the forward one rearward which opens the bolt, let go of it and it slams forward, the axis pin of the disc catches the trigger.
The forward gun moves the rear one, rearwards cocks that, it moves forward before the front one hits the trigger catch again, so it fires first this time they then operate independently of each other via there own recoil until empty.
The mount drawing only shows one gun like, can’t draw 3d etc.
A barrel mount not shown, still if you made an attachment to achieve the function aforementioned.
Might work, he he.
Er… Confusing myself now, the separate discs run parallel to each other but the levers actuating studs are different for each i.e. holding one gun forward of the other giving the individual cycles aye that’s it in theory.
Hmmm, well I think it might have some relation to the Gast gun minus the Winchesters in principle possibly, anyway I can examine the Gast gun more now because of the information provided cheers!
Well if you just had one disc, with both guns mounted parallel on either side of it in the same positions. Might simply provide a method to fire two lever actions automatically at once, he he.
Confused myself in regards having one cock the other, it’s pretty pointless in this format.
The Gast gun’s technology is covered in depth in Chinn, although I forget which volume (sorry). I doubt it was ever a numerically significant gun, but it would seem to have unplumbed potential for high-rate-of-fire air-cooled systems.
Interesting fact about the airplane. We don’t know how big the fuel tank was, but the empty weight was 1848 lbs and the available payload with full fuel over 700 — given two 180 pound crewmen, and a wingspan I’d estimate at 35 feet, those are quite good numbers for a smallish aircraft even today. (And judging from surving uniforms, a WWI airman was almost certainly closer to 140 lbs than 180). We look at those spindly airplanes from a century on and forget that this was the high-tech machinery of the era.
We don’t know if the guns and ammo come out of the payload (they probably do) or are reckoned as part of the empty weight of the plane (as the guns, but not the ammo, would be in WWII).
It’s also interesting that nowadays individual airplanes are weighed every time they’re modified, and so no two are exactly the same on empty weight or payload. But in WWI, they used nice round numbers.
A brilliant German fellow named Achim Engels spent a decade or so working towards a living-history museum where WWI Fokkers would be made using period tools and technology. He financed his dream by building dead-on accurate aircraft made that same way; he even sewed fabric covering envelopes with the exact model of sewing machine the Fokker plant used in 1916. Even those of you who are not plane geeks would have loved him. In the end, he burnt out on the project (somebody appears to have ripped him off over something, and he just gave up and the project imploded spectacularly).
Engels did publish some short works on armaments and on the different synchronization gear. Fascinating stuff. Fokker and Constantinesco, among others, solved the problem different ways.
Very good post, Kevin — thank you. Yes, the use of Anthony Fokker’s interrupter gear on his E.1-E.IV monoplanes ( the Fokker “Eindecker” ) was a major advance in the early days of World War One aircraft technology. The timing could not have come at a worse time for the Allied air forces ( July 1915 ) and resulted in a level of battlefield air superiority for the German Air Service — and an almost unprecedented slaughter of British and French aircrews — that has seldom since been equaled. It took until nearly mid-1916 before newer Allied designs were able to achieve parity and end the “Fokker Scourge”.
What a pity about Engels and his endeavours, though. Historical aviation is that much poorer with the demise of his efforts.
The Gast MG17 ( not to be confused with the more well-known Solothurn-Rheinmetall MG17 7.92mm aircraft MG ) was designed by Ing. Carl Gast of the Vorwerk Company, Bremen-Eberfeld, Germany. It was a twin-barreled air-cooled machine gun that actually comprised two complete guns mounted side-by-side with their breechblocks tied together via a linkage mechanism so that they would fire alternately, i.e., when the breech on one was open, the breech on the other would be in the closed position. The weapon was capable of a cyclic rate-of-fire of 1800 rds./min. with an acceptable degree of reliability, and was fed by large vertically-mounted spring-operated drum magazines on either side that were not interchangeable ( left- or right-handed feed only ). Only about 500 ( out of a projected 5000 ) were made before World War One ended, so the gun did not see widespread service. Ian Hogg estimates that fewer than a dozen examples survive to this day.
For more detailed information, try starting off with the following :
1. Machine Guns by Ian V. Hogg ( Krause Publications, Iola, WI, 2002 ; Library Of Congress Catalog Number 2001091076 ) — Ref. Pg. 84 ( description ) and Pgs. 78-79 ( photograph and cutaway diagrams )
4. riseofflight.com/forum/viewtopic.php?t=21797 — This article also has some very good information on the Parabellum aircraft MG featured in this FW post.
5. http://www.google.com/patents/US1477115 — This should provide you with all the design, technical and mechanical details you could possibly wish for. Also, per our friend Keith : Keith, if you are reading this, you might find it quite interesting ( if you already haven’t perused the document ).
7. en.wikipedia.org/wiki/Gast_gun — Good information, but as is usual with Wikipedia, may be subject to occasional anomalies and corrections.
Hope this helps you and other FW readers a bit. Perhaps someone else on this site may have seen a surviving example of the Gast in a museum and can provide more links?
I had written with an extensive list of recommended articles on the Gast MG17 aircraft machine-gun ( not to be confused with the Solothurn-Rheinmetall MG17 aircraft MG of later years ), but for some reason it has not gone through on FW.
Therefore, to reiterate, the Gast MG17 was designed by Ing. Carl Gast of the Vorwerk Company of Bremen-Eberfeld, Germany. It comprised two machine-guns mounted side-by-side, and their breechblocks were tied together via a mechanical linkage that fired the guns alternately, i.e., when one breech was closed, the other was in the open position. The guns were fed by large, top-mounted drum magazines on either side that were not interchangeable ( left-side drums were strictly for the left-hand gun and right-hand drums would only work with the right-hand gun ). The cyclic rate of fire reached 1800 rds./min. with an acceptable level of reliability in its final form.
About 500 guns were produced before the end of World War One ( out of the 5000 originally envisaged ), so they never saw widespread service as anticipated. Ian Hogg estimates that fewer than one dozen known examples survive to this day around the world, so it is a truly rare weapon.
I had provided several links for you on the subject of the Gast MG outside of Chinn in the previous post, but rather than have to go through them all again I would recommend just these two :
1. Machine Guns by Ian V. Hogg ( Krause Publications, Iola, WI, 2002 ; Library Of Congrss Publication Number 2001091076 ) — Ref. Pg. 84 for a general description and history, and Pgs. 78-79 for a photograph and cutaway diagrams.
2. http://www.google.com/patents/US1477115 — This should provide you with most of the detailed, in-depth design, technical and mechanical information on the Gast MG.
Also : Keith, if you haven’t already examined it, you might find Item #2 interesting ( I know firearms patents are one of your strongest interests, based on previous FW comments ).
Hope this helps a little. Perhaps some of the readers on FW will be able to provide links to where they might have seen a Gast MG in a museum or display?
Thanks for reminding us Earl!
I know this topic was discussed some time ago, but it faded (at least in mine) memory. So, here it is: deja-vu. You served PDs inquiry lot better than I was able to do….
There’s a Huges Heligun mentioned on this website, maybe that’s kind of a Gast mechanism.
Check out the “EX-17 Heligun” article dated October 31st, 2011 on FW. Ian included a complete 120+ page official technical test report on the Heligun ( including performance comparisons with the General Electric M134 7.62mm Minigun ) compiled by Hughes in 1966 that should provide you with a wealth of information should you decide to pursue the subject. You can download the report in Adobe PDF format as well.
As a whole, the Heligun was in many ways a miniature, American-designed rifle-caliber ( 7.62mm vs. 23mm caliber ) counterpart to the twin-barreled, highly-successful Soviet Gryazev-Shipunov GSh-23 aircraft cannon which entered Eastern-bloc service in 1965. It was gas-operated ( and therefore not dependent on an external power source ), weighed about half as much as a Minigun and delivered a similar cyclic rate of fire ( 4000-6000 rds./min.). However, Hughes Aircraft could not quite achieve sufficient reliability in terms of MTBS ( Mean Time Between Stoppages ) to fully justify replacement of the already well-established and proven Minigun in spite of the Heligun’s other advantages, and the project was eventually dropped.
Fascinating subject Earl 🙂
Note: the machine gun working on Gast principle are rare in West countries but were used in Soviet Union – everyone which is interesting in Soviet military aviation know GSh-23 cannon, but Silin designed their Gast-principle twin-barreled machine gun in 1930s (7,62x54R) http://guns.wikia.com/wiki/Silin_gun it was gas-operated and fire 6000RPM. It was designated ЦКВСВ-19.
And when we are discussing aircraft twin-barrel don’t forget about Gebauer machine gun.
I seem to recall a discussion on FW to that effect where we also covered the ShKAS aircraft MG. It was quite a while back, though.
@ Earl and Daweo; I am glad you brought up GSh-23. I had that thought too but did not carry thru with it. That weapon was indeed successful and widespread, lately mostly on combat helicopters. Czech aircraft armament company (happen to be out of business for some time) have rebuild it for 20mm M60 Vulcan cartridge, intended for L-139 Alca ground support plane. It is really interesting where the Gast gun idea ended up… and maybe has some future to it.
That is definitely an interesting conversion. From what I understand, the larger 23mm x 115 Soviet cartridge generates a typical chamber pressure of 42000-43000 psi ( perhaps more in higher-powered loadings ) while the smaller 20mm x 102 American cartridge generates chamber pressures of around 60000 psi or higher. For the Czechs to undertake such a conversion with confidence probably speaks volumes not only for their engineering abilities but also the sheer strength and durability of the GSh-23 design.
There was some criticism on subject of value of reduced calibre, but this has obviously Nato logistics connection behind it. And yes, the plane is L-159, not L-139.
@Earl Liew:
When you have said ShKAS I recall that I have said of SN (Savin-Norov) Machine Gun (which itself has a very interesting, unique principle of operation: gas-forward-gear-wheel-operation) but when I’ve search for more info of SN I have found this: http://raigap.livejournal.com/130053.html
It describes both SN and Silin gun and say that the Silin designed machine gun using the developed idea of SN. And now something very interesting:
“Такой двуствольный пулемёт СИ экспонировался примерно в 1981-1982г. в музее Одесского военного округа на ул.Пироговской, правда без таблички и бабушка в зале объяснить что это такое не могла.”
i.e. The one twin-barrel Silin machine gun was exposed in 1981-1982 in museum of Odessa Military District, Пироговская street in Odessa, but as a unknown machine gun – nobody know “what is it?”.
Thanks for the additional information Daweo — very interesting, indeed!
Last year one of the big auctions, I think RIA’s, had an absolutely gorgeous Parabellum or maybe a dual-mount? ISTR it went for large money, something like $28k.
This is an Albatros C.III, if I’m not mistaken. The main issues of aircraft design are material selection, general layout (with dimensions, given the material properties, engine power, and weights), engine power, and safety (duh). Here, the exhaust manifold of the inline engine has its outlet over the leading edge of the upper wing. This supposedly decreases the likelihood of any inefficient (or damaged) engine combustion leading to flames in the exhaust gas setting the fuselage on fire (where’s the #%^*^&*$ extinguisher?), but the arrangement reduces pilot visibility and creates lots of drag, to say nothing of the wing-mounted radiator being vulnerable to attack. The main fuel tank of this Albatros plane is under the pilot’s seat, not very comforting when you realize that the fuel tank has no protective coating. That Parabellum may be the only defense for the crew, unless there’s a synchronized MG-08 for the pilot. Did I miss anything (apart from the plane, since I’m a rotten shot)?
My friend, you have just awakened some fond boyhood memories for me with your mention of the “Biggles” series, which was written by an ex-RFC pilot, Captain W.E. Johns. Johns was a very good writer who somehow managed to tread that fine line between stirring the imaginations of young lads regarding the spirit of pioneering wartime aviation and avoidance of romanticizing the horrific realities of the front-line air battles in the Great War. More than one source has acknowledged that Johns inspired a whole new generation of budding airmen in the 1920’s and 1930’s from all walks of life, and from both sides.
What a coincidence Earl, see here we go again – time and place continuum.
This particular literature was my reading by winter evenings since I was about 10yrs old. My farther used to buy it (as sequels) in years 1937-38. He wished to be a military pilot, but with incoming war it did not work out (only ethic Germans were trusted). After the war he tried again and without luck, but he kept his interest in flying and used to take me to air-shows. I made it just a tiny step further and learned to fly on glider.
Thanks for sharing, Denny. It was good to read about your flying experiences, too. While power-driven aircraft have certain obvious advantages, there is nothing quite like the serenity of soaring in a glider, accompanied by nothing more than the sound of the wind. I am happy to hear that you have had the privilege to do this in your lifetime.
While I dearly wish that your father could have fulfilled his dreams of becoming a military pilot, there is also a part of me which is glad that he didn’t, given the casualty rate of airmen at the time.
Not so much lately; I guess it has worn off with me for some time. I am actually more interested in amateur kit-builders planes more than anything else. I suppose down in States is more opportunity to follow on this; Oshkosh being notoriously known. I just needs to make decision and go to see them.
My own flying period including learning requested theories (aerodynamics, meteorology…) was actually only 3 years, just before my 20th birthday, so its quite a while back. As I recall I did not feel apprehension about doing it at the least (my mother had objections). It was sheer nirvana – as you say soaring nearly soundless.
Most mothers would object to this sort of activity, anyway :).
An old shipmate of mine (submarine sailor from the late 70s) is very, very slowly (one paycheck at a time) building a Nieuport biplane in his garage in Indiana. Last pictures I saw he had the frame for the body and tail connected and was getting started on the wings. Considering some of the less-than-brilliant stunts that particular QM2(SS) pulled in our glory days, I’m torn between rooting for him to get it airborne and dreading what will happen if he ever does.
But some of the comments about modern dual-mounts reminds… at one point I was offered a good deal on an “almost running” 1970s VW Thing (civilian Kubblewagon (sp?)) and was very tempting (despite considerable experience with good deals on cool vehicles that are “almost running”) due to the notion of buying right- and left-hand 12-gauge Remington 1100 semi-autos, fitting them with extended magazines and pistol grips, and welding up a dual pintle mount for the back seat of the Thing. Guess that would work for a replica biplane as well, should I find myself in another situation where I have more money than sense. (The norm is to have not very much of either….)
Hi, Jim :
Do you know if it’s a Nieuport 17 or an earlier version? Thanks in advance.
Really?! Mon Dieu,- my all time favourite single seater from WWI! Lets assume it is Model 17…. here is one for reference, in the air: http://www.youtube.com/watch?v=GLpZET6_wxA
I believe it was also flown by American airmen along with SPADs – name Rieckenbaker is coming to mind.
So beautiful, so purposeful and yet so elegant and slender, like charming dancer…. oh MD!
While building replicas, the challenges are many and I am sure your mate is well into it. One major one is of course reliable engine. Some time ago I ran into page in which a German (I believe) small firm was offering original Oberursel, virtually identical to 9-cylinder rotary Gnome-Rhone. This is absolute must to see for every mechanics lover! And not to forget – to run it properly with all the right aroma and unavoidable ‘overspray’ you need genuine Castor oil!
“Biggles learns to fly” was the first book which I actually read right through, and it was the first book which I actually enjoyed reading.
I once met a former boat builder who had worked as one of the volounteers building the Shuttleworth collection’s Sopwith tri plane. Old T. O M. Sopwith took a very close interest in the project, and was so impressed with how closely the project had followed the original works drawings that he declared it to be “late production” rather than a reproduction, and awarded it a serial number. http://www.shuttleworth.org/shuttleworth-collection/aircraft-details.asp?ID=7
The reason for Bi and Tri plane layout was largely structural, the lattice girder fromed by the biplane structure is incredibly strong.
When Fokker was developing his “ein dekker” he had serious problems with wing spars breaking, they were strong enough in static loading tests with sand bags, but snapped in aerial testing. Official help from the air ministry boffins suggested strengthening the rear spar – which actually made things worse. Fokker then counter intuitively went to a lighter, more flexible rear spar which cured the problem sufficient for military use, however the plane still remained less structurally safe than its less aerodynamic biplane contemporaries. I gather that in the inter war period, several national governments banned monoplanes as inherently unsafe.
I’ve never flown in one of the WWi era designs, speaking to people who have, I’m told that they are absolute little [anatomical orifice of your choice]s for stalling and spinning with next to no warning,
and, the narrow (and usually un sprung)tail dragger undercarriage makes them particularly prone to ground loops on landing.
The radial rotary engines fascinated me for a lot of years.
That Albatross, with its in line engine and high exhaust, at least spared the crew from the constant mist of castor oil (hence they didn’t need a long scarves to wipe the oil off their goggles with – and it deprived them of an excuse for soiling their undies)
Up to the Bentley BR1 and BR2 rotaries with their aluminium cylinder jackets and pressed in cast iron cylinder liners, rotaries used a thin cup washer as the top piston ring, to accomodate distortion of the thin steel cylinder walls due to uneven heating and cooling. As a result, those rotaries required a full strip down and rebuild after every 8 to 12 hours of running.
Apart from the Gnome “Monosoupape” (single valve – it used the same cylinder head valve for exhaust and inlet, simillar to the inter war Guiberson radial diesel) all of the rotaries also had their crank cases full of explosive mixture – or hopefully explosive, as the air throttle and the fuel nozzle were controlled by different levers – when you opened the throttle, if you didn’t also open the fuel fast enough, the engine stopped firing, mixture had to be adjusted to where it started firing again, and then leaned off to where it ran smoothly.
The Gnome Monosoupape rotary was a constant speed engine, power could only be controlled by switching the ignition on and off, and relying on the momentum of the spinning prop and cylinders to start it again when the ignition was switched back on.
Add to all of those complications that it was well into WWi before a method of reliably recovering from spins began to be taught. The guy who worked it out, didn’t realize that no one else knew how to recover from a spin, and so for a long time, never thought to pass the information on.
Thanks for pitching in your part of knowledge Keith!
The issue of “aero-elasticity” as it had been know for some time was not known then. while attempting to make construction as rigid as possible, they were creating problem in opposite direction – making it fragile. Same applies for ships; I have seen once a video taken form bridge on rough sea and it was very visible how it was beautifully flexing. Without that ability it would probably break into pieces.
Speaking of engines; there is quite a bit of it to study and part of La Rome http://en.wikipedia.org/wiki/Le_Rh%C3%B4ne and oberursel there were also other German, British and Italian companies coming with their products. As usual, there is the dispute ‘who was the first’, but lets assume it was indeed La Rhone with its previous developments, as you write. I looked at comparative data of most commonly used La Rhone and Oberursel and found they are similar, but not the same. While output was comparable, the bore and stroke were not he same (with German engine having bigger bore and shorter stroke). As far as current replicas, the prime supplier seem to be Australian Rotec with their 2.8 litre 7-cylider radial (but not rotary) engines. They have substantially less displacement than WWI originals but they are economical and foolproof not to mention not creating oil mist.
Hi Denny,
The engineering history of ships, planes and road vehicles absolutely fascinating. There are a couple of books by the old prof of nautical engineering at Glasgow G.E. Gordon (“new science of strong materials” and “structures”)
They’re a great understandable introduction to those aspects of engineering and still interesting for people (like yourself) who already have a strong engineering background. I got the Fokker example from him.
Gordon did his degree between the wars, and said that the Griffiths theories of stress concentrators and crack propagation remained controversial and were not taught in naval architecture courses for many years, during which ships continued to snap in half (and they still do snap in half!)
He was also old enough and wise enough to be deeply sceptical of “new” materials, in one of his works he points out that (apart from its problems of warping and rot) spruce and balsa wood are superior for some aircraft uses to carbon fibre.
Your comments about bore and stroke differences between the Oberusal and La Rhone engines is very interesting, as the Oberusal began as a clone of the La Rhone.
It was late 1990s when I got my copy direct from him (he kindly posted it to me without asking to be paid – I sent him a cheque in the next post, that kind of honesty and trust seems to engender great respect 🙂 )
His coverage of the last gasp of the radial rotary with the British and German efforts of going to 200 hp output with minimal gyroscopic effects is fascinating.
British bureaucrats had been led into putting hope in an unproven static radial, the ABC “Dragonfly” which spectacularly failed to deliver the hoped for performance and reliability (reports of cylinder heads glowing red during testing!).
As an emergency measure W O Bentley was been given the project to wring 200 HP out of a proven Clerget design, which he did by increasing capacity and by using conventional cast liners, aluminium pistons (very unconventional at that time) and succeded in producing 200hp with less gyroscopic effects than the parent 130 hp Clerget.
Apparently Bentley met considerable resistance and resentment at the factory he was posted to to undertake his work.
The Seimens Halske, sought to increase output by increasing revs but without increasing aerodynamic losses due to the spinning cylinders, or raising prop revs…
They achieved that by installing a differential gear at the back of the engine, so that the crank turned one way at around 1000 RPM, while the cylinders and prop rotated the other way at the same speed – clever fellows those Germans.
I wasn’t aware of the small Aussie static radial. I did see some of the work in progress in the early 1990s by a bunch of guys who were using air cooled cylinders and pistons, sourced from a 1970s Daf car, to make a small radial (I was between girlfriends at the time – they tend not to be sympathetic to me spending time (or money!) on such interests) I don’t know if the project ever came to anything, spouses, bank managers and day job employers all have a nasty habit of running out of patience before such projects are completed.
There seem to be some very nice inverted inline engines coming out of Czechia at the moment. They look like good material for authentic looking replacements for De Haviland Gypsy engines in Moths, Austers etc
Denny, it looks like Camden are selling copies of Lew Blackmore’s book on making a 1/4 scale working model of a Bentley BR2, at 1/10th the price amazon is asking.
they also have a youtube video of one of the completed 1/4 scale engines being started and flown
Yes Keith, it is truly enjoyable to exchange ideas with you… and in more than one area!
You are also absolutely right about British pioneering efforts – they are not forgotten. As matter of fact The radial engines coming from your country between wars were likely on peak od state-of-art of the day.
Czech plane engine industry had its start start-up already during “First republic”. The Walter factory became quite proficient and their inverted six such as Walter Minor were mounted into Zlin/Trener line of sports aircrafts.
I will pursue the links you provided – thank you kindly Sir!
Great slideshow ! Amazing how “techie” they were back then. My (German) great aunt showed me a picture of her grandfather – a well off farmer who served in WW 1 – I expected to see a well-dressed guy w.spiked helmet in a studio photo , but there he was – in a greatcoat with a big version of the WW2 helmet(the 1916) sitting in an old west style wagon sans canvas top..Looked for all the world like sergeant Schultz, used to take supplies forward in the morning and haul out the wounded(and perhaps the dead) on his way back…
Like the originals they tend to be difficult to fly. Part of it is that a well designed fighter (then as now) must be highly maneuverable, so maneuverability is weighted over stability.
The repros are either mostly accurate. (An example is Engels’s work, which Antony Fokker could only tell from his own by the higher quality and better finish) or they are eyeball accurate, with adjustments made in materials and design.
A good example of the latter type is Robert Baslee’s many replica kits, available at http://airdromeaeroplanes.com/. The “machine guns” are generally composite copies — very lightweight, and perfectly accurate if you don’t need them to shoot. There’s a shop in Pennsylvania that makes them.
Your mention of Professor Gordon’s “The New Science Of Strong Materials” prompted me to pull out my old copy of that same book ( which I’ve kept since my college days ) and re-read it all over again. Ah, what memories — many thanks, my friend!
Great photo! The Parabellum was a very interesting branch of the Maxim tree. I am still looking for a lock to go with my feed lock should anyone have one for sale or trade!
Joe
Fantastic, this had been my area of interest for ‘decades’ – well mostly in past. The Parabellum gun had been used almost exclusively by observes, as I recall. The one shown with drum feed looks formidable; I would not want to argue with its operator.
Here is little reading on the subject and answer why it was used primarily by observers – it was hard to make it work as synchronised.
http://www.wwiaviation.com/german_guns.html
Interesting stuff Denny, do you have any information on the Gast gun?
Not at hand at the moment P.doughboy, but you can probably find plenty of info on net. I think of it as one of most intriguing and in fact it is to my surprise, it did not get into wider use. It came probably little too late into the game.
I have found something’s about it off the internet.
Chinn, I presume that’s a book Kevin I’ll have a look for that cheers.
I was briefly pondering the notion that two Winchesters on a staggered mounting operating two sort of slide fire stocks which act independently of one another, in conjunction with a rotating cam/stud arrangement placed between the two which would operate the actions separately “said contraption would perhaps partially resemble a reel off a fishing rod” with protruding rods depressing either trigger at the appropriate point of each rifles cycle after initially starting off the process manually, might reactivate the concept in the U.S for novelty purposes.
I like WW1 planes, something attractive about there apparent simplicity. Wouldn’t fancy flying in one firing machine guns at one another though particularly, he he.
You might be interested to hear, PD that my fancy in flying things was caught be cheap war time sequel named Bigless – Captain of Camel Fighters. It was in translation of course and it originated from time shortly before WWII.
Soon after that I was able to read similar, but more personal account from Ernst Udet, the German Ace, in form of his memoirs called “My life of pilot”. That was starting point for me.
I got a game for my mobile phone, Rise of glory you’d like that WWI fighter plane game it’s good he he.
PD;
http://www.milsurps.com/content.php?r=347-The-Machine-Gun-%28by-George-M.-Chinn
All volumes, free, in PDF. Unless your DSL is faster than mine, figure on spending about 2 hours to download.
cheers
eon
Let me tell you Sir (eon)… you are a genius. Thank you very much!
Here is a link to a picture in my photo bucket album of a “Gast” type action using two Winchesters as I mentioned above if the link works.
http://i1142.photobucket.com/albums/n607/patrickmurphy3/1a/1b/W_zpsd7bcdc37.png
Well the link worked so I will briefly explain my drawing, the idea is for a mount to be constructed which would hold two 45/70 Lever action rifles while allowing them to be detached from it again easily.
The guns are mounted left and right of each other on their own discs, a lug on the forward weapons barrel mount catches the lug on the rear weapons one when it fires…
Pushing the gun back, to fire initially you load both guns pull the forward one rearward which opens the bolt, let go of it and it slams forward, the axis pin of the disc catches the trigger.
The forward gun moves the rear one, rearwards cocks that, it moves forward before the front one hits the trigger catch again, so it fires first this time they then operate independently of each other via there own recoil until empty.
The mount drawing only shows one gun like, can’t draw 3d etc.
A barrel mount not shown, still if you made an attachment to achieve the function aforementioned.
Might work, he he.
Er… Confusing myself now, the separate discs run parallel to each other but the levers actuating studs are different for each i.e. holding one gun forward of the other giving the individual cycles aye that’s it in theory.
Hmmm, well I think it might have some relation to the Gast gun minus the Winchesters in principle possibly, anyway I can examine the Gast gun more now because of the information provided cheers!
Well if you just had one disc, with both guns mounted parallel on either side of it in the same positions. Might simply provide a method to fire two lever actions automatically at once, he he.
Confused myself in regards having one cock the other, it’s pretty pointless in this format.
The Gast gun’s technology is covered in depth in Chinn, although I forget which volume (sorry). I doubt it was ever a numerically significant gun, but it would seem to have unplumbed potential for high-rate-of-fire air-cooled systems.
Interesting fact about the airplane. We don’t know how big the fuel tank was, but the empty weight was 1848 lbs and the available payload with full fuel over 700 — given two 180 pound crewmen, and a wingspan I’d estimate at 35 feet, those are quite good numbers for a smallish aircraft even today. (And judging from surving uniforms, a WWI airman was almost certainly closer to 140 lbs than 180). We look at those spindly airplanes from a century on and forget that this was the high-tech machinery of the era.
We don’t know if the guns and ammo come out of the payload (they probably do) or are reckoned as part of the empty weight of the plane (as the guns, but not the ammo, would be in WWII).
It’s also interesting that nowadays individual airplanes are weighed every time they’re modified, and so no two are exactly the same on empty weight or payload. But in WWI, they used nice round numbers.
A brilliant German fellow named Achim Engels spent a decade or so working towards a living-history museum where WWI Fokkers would be made using period tools and technology. He financed his dream by building dead-on accurate aircraft made that same way; he even sewed fabric covering envelopes with the exact model of sewing machine the Fokker plant used in 1916. Even those of you who are not plane geeks would have loved him. In the end, he burnt out on the project (somebody appears to have ripped him off over something, and he just gave up and the project imploded spectacularly).
Engels did publish some short works on armaments and on the different synchronization gear. Fascinating stuff. Fokker and Constantinesco, among others, solved the problem different ways.
Very good post, Kevin — thank you. Yes, the use of Anthony Fokker’s interrupter gear on his E.1-E.IV monoplanes ( the Fokker “Eindecker” ) was a major advance in the early days of World War One aircraft technology. The timing could not have come at a worse time for the Allied air forces ( July 1915 ) and resulted in a level of battlefield air superiority for the German Air Service — and an almost unprecedented slaughter of British and French aircrews — that has seldom since been equaled. It took until nearly mid-1916 before newer Allied designs were able to achieve parity and end the “Fokker Scourge”.
What a pity about Engels and his endeavours, though. Historical aviation is that much poorer with the demise of his efforts.
The Gast MG17 ( not to be confused with the more well-known Solothurn-Rheinmetall MG17 7.92mm aircraft MG ) was designed by Ing. Carl Gast of the Vorwerk Company, Bremen-Eberfeld, Germany. It was a twin-barreled air-cooled machine gun that actually comprised two complete guns mounted side-by-side with their breechblocks tied together via a linkage mechanism so that they would fire alternately, i.e., when the breech on one was open, the breech on the other would be in the closed position. The weapon was capable of a cyclic rate-of-fire of 1800 rds./min. with an acceptable degree of reliability, and was fed by large vertically-mounted spring-operated drum magazines on either side that were not interchangeable ( left- or right-handed feed only ). Only about 500 ( out of a projected 5000 ) were made before World War One ended, so the gun did not see widespread service. Ian Hogg estimates that fewer than a dozen examples survive to this day.
For more detailed information, try starting off with the following :
1. Machine Guns by Ian V. Hogg ( Krause Publications, Iola, WI, 2002 ; Library Of Congress Catalog Number 2001091076 ) — Ref. Pg. 84 ( description ) and Pgs. 78-79 ( photograph and cutaway diagrams )
2. http://www.ww2aircraft.net/forum/aviation/why-gast-gun-never-used-aircraft-during-wwii-34027.html
3. forum.axishistory.com/viewtopic.php?f=71&t=202027
4. riseofflight.com/forum/viewtopic.php?t=21797 — This article also has some very good information on the Parabellum aircraft MG featured in this FW post.
5. http://www.google.com/patents/US1477115 — This should provide you with all the design, technical and mechanical details you could possibly wish for. Also, per our friend Keith : Keith, if you are reading this, you might find it quite interesting ( if you already haven’t perused the document ).
6. firearmshistory.blogspot.com/2013/01/unusual-firearms-gast-gun.html
7. en.wikipedia.org/wiki/Gast_gun — Good information, but as is usual with Wikipedia, may be subject to occasional anomalies and corrections.
Hope this helps you and other FW readers a bit. Perhaps someone else on this site may have seen a surviving example of the Gast in a museum and can provide more links?
Hi, P.D. :
I had written with an extensive list of recommended articles on the Gast MG17 aircraft machine-gun ( not to be confused with the Solothurn-Rheinmetall MG17 aircraft MG of later years ), but for some reason it has not gone through on FW.
Therefore, to reiterate, the Gast MG17 was designed by Ing. Carl Gast of the Vorwerk Company of Bremen-Eberfeld, Germany. It comprised two machine-guns mounted side-by-side, and their breechblocks were tied together via a mechanical linkage that fired the guns alternately, i.e., when one breech was closed, the other was in the open position. The guns were fed by large, top-mounted drum magazines on either side that were not interchangeable ( left-side drums were strictly for the left-hand gun and right-hand drums would only work with the right-hand gun ). The cyclic rate of fire reached 1800 rds./min. with an acceptable level of reliability in its final form.
About 500 guns were produced before the end of World War One ( out of the 5000 originally envisaged ), so they never saw widespread service as anticipated. Ian Hogg estimates that fewer than one dozen known examples survive to this day around the world, so it is a truly rare weapon.
I had provided several links for you on the subject of the Gast MG outside of Chinn in the previous post, but rather than have to go through them all again I would recommend just these two :
1. Machine Guns by Ian V. Hogg ( Krause Publications, Iola, WI, 2002 ; Library Of Congrss Publication Number 2001091076 ) — Ref. Pg. 84 for a general description and history, and Pgs. 78-79 for a photograph and cutaway diagrams.
2. http://www.google.com/patents/US1477115 — This should provide you with most of the detailed, in-depth design, technical and mechanical information on the Gast MG.
Also : Keith, if you haven’t already examined it, you might find Item #2 interesting ( I know firearms patents are one of your strongest interests, based on previous FW comments ).
Hope this helps a little. Perhaps some of the readers on FW will be able to provide links to where they might have seen a Gast MG in a museum or display?
Thanks for reminding us Earl!
I know this topic was discussed some time ago, but it faded (at least in mine) memory. So, here it is: deja-vu. You served PDs inquiry lot better than I was able to do….
There’s a Huges Heligun mentioned on this website, maybe that’s kind of a Gast mechanism.
Check out the “EX-17 Heligun” article dated October 31st, 2011 on FW. Ian included a complete 120+ page official technical test report on the Heligun ( including performance comparisons with the General Electric M134 7.62mm Minigun ) compiled by Hughes in 1966 that should provide you with a wealth of information should you decide to pursue the subject. You can download the report in Adobe PDF format as well.
As a whole, the Heligun was in many ways a miniature, American-designed rifle-caliber ( 7.62mm vs. 23mm caliber ) counterpart to the twin-barreled, highly-successful Soviet Gryazev-Shipunov GSh-23 aircraft cannon which entered Eastern-bloc service in 1965. It was gas-operated ( and therefore not dependent on an external power source ), weighed about half as much as a Minigun and delivered a similar cyclic rate of fire ( 4000-6000 rds./min.). However, Hughes Aircraft could not quite achieve sufficient reliability in terms of MTBS ( Mean Time Between Stoppages ) to fully justify replacement of the already well-established and proven Minigun in spite of the Heligun’s other advantages, and the project was eventually dropped.
Fascinating subject Earl 🙂
Note: the machine gun working on Gast principle are rare in West countries but were used in Soviet Union – everyone which is interesting in Soviet military aviation know GSh-23 cannon, but Silin designed their Gast-principle twin-barreled machine gun in 1930s (7,62x54R) http://guns.wikia.com/wiki/Silin_gun it was gas-operated and fire 6000RPM. It was designated ЦКВСВ-19.
And when we are discussing aircraft twin-barrel don’t forget about Gebauer machine gun.
Hi, Daweo :
I seem to recall a discussion on FW to that effect where we also covered the ShKAS aircraft MG. It was quite a while back, though.
@ Earl and Daweo; I am glad you brought up GSh-23. I had that thought too but did not carry thru with it. That weapon was indeed successful and widespread, lately mostly on combat helicopters. Czech aircraft armament company (happen to be out of business for some time) have rebuild it for 20mm M60 Vulcan cartridge, intended for L-139 Alca ground support plane. It is really interesting where the Gast gun idea ended up… and maybe has some future to it.
That is definitely an interesting conversion. From what I understand, the larger 23mm x 115 Soviet cartridge generates a typical chamber pressure of 42000-43000 psi ( perhaps more in higher-powered loadings ) while the smaller 20mm x 102 American cartridge generates chamber pressures of around 60000 psi or higher. For the Czechs to undertake such a conversion with confidence probably speaks volumes not only for their engineering abilities but also the sheer strength and durability of the GSh-23 design.
Here is additional info on that Czech GSh-23 version: http://en.valka.cz/viewtopic.php/t/38807
There was some criticism on subject of value of reduced calibre, but this has obviously Nato logistics connection behind it. And yes, the plane is L-159, not L-139.
@Earl Liew:
When you have said ShKAS I recall that I have said of SN (Savin-Norov) Machine Gun (which itself has a very interesting, unique principle of operation: gas-forward-gear-wheel-operation) but when I’ve search for more info of SN I have found this:
http://raigap.livejournal.com/130053.html
It describes both SN and Silin gun and say that the Silin designed machine gun using the developed idea of SN. And now something very interesting:
“Такой двуствольный пулемёт СИ экспонировался примерно в 1981-1982г. в музее Одесского военного округа на ул.Пироговской, правда без таблички и бабушка в зале объяснить что это такое не могла.”
i.e. The one twin-barrel Silin machine gun was exposed in 1981-1982 in museum of Odessa Military District, Пироговская street in Odessa, but as a unknown machine gun – nobody know “what is it?”.
Thanks for the additional information Daweo — very interesting, indeed!
Last year one of the big auctions, I think RIA’s, had an absolutely gorgeous Parabellum or maybe a dual-mount? ISTR it went for large money, something like $28k.
This is an Albatros C.III, if I’m not mistaken. The main issues of aircraft design are material selection, general layout (with dimensions, given the material properties, engine power, and weights), engine power, and safety (duh). Here, the exhaust manifold of the inline engine has its outlet over the leading edge of the upper wing. This supposedly decreases the likelihood of any inefficient (or damaged) engine combustion leading to flames in the exhaust gas setting the fuselage on fire (where’s the #%^*^&*$ extinguisher?), but the arrangement reduces pilot visibility and creates lots of drag, to say nothing of the wing-mounted radiator being vulnerable to attack. The main fuel tank of this Albatros plane is under the pilot’s seat, not very comforting when you realize that the fuel tank has no protective coating. That Parabellum may be the only defense for the crew, unless there’s a synchronized MG-08 for the pilot. Did I miss anything (apart from the plane, since I’m a rotten shot)?
You might be right, an elegant machine by any means.
http://www.finemodelworks.com/arizona-models/reference/Thumbs/Aircraft/Germany/Albatros/C3/C3.html
@ Denny :
My friend, you have just awakened some fond boyhood memories for me with your mention of the “Biggles” series, which was written by an ex-RFC pilot, Captain W.E. Johns. Johns was a very good writer who somehow managed to tread that fine line between stirring the imaginations of young lads regarding the spirit of pioneering wartime aviation and avoidance of romanticizing the horrific realities of the front-line air battles in the Great War. More than one source has acknowledged that Johns inspired a whole new generation of budding airmen in the 1920’s and 1930’s from all walks of life, and from both sides.
What a coincidence Earl, see here we go again – time and place continuum.
This particular literature was my reading by winter evenings since I was about 10yrs old. My farther used to buy it (as sequels) in years 1937-38. He wished to be a military pilot, but with incoming war it did not work out (only ethic Germans were trusted). After the war he tried again and without luck, but he kept his interest in flying and used to take me to air-shows. I made it just a tiny step further and learned to fly on glider.
Thanks for sharing, Denny. It was good to read about your flying experiences, too. While power-driven aircraft have certain obvious advantages, there is nothing quite like the serenity of soaring in a glider, accompanied by nothing more than the sound of the wind. I am happy to hear that you have had the privilege to do this in your lifetime.
While I dearly wish that your father could have fulfilled his dreams of becoming a military pilot, there is also a part of me which is glad that he didn’t, given the casualty rate of airmen at the time.
Do you still go to air shows where you are?
Not so much lately; I guess it has worn off with me for some time. I am actually more interested in amateur kit-builders planes more than anything else. I suppose down in States is more opportunity to follow on this; Oshkosh being notoriously known. I just needs to make decision and go to see them.
My own flying period including learning requested theories (aerodynamics, meteorology…) was actually only 3 years, just before my 20th birthday, so its quite a while back. As I recall I did not feel apprehension about doing it at the least (my mother had objections). It was sheer nirvana – as you say soaring nearly soundless.
Most mothers would object to this sort of activity, anyway :).
An old shipmate of mine (submarine sailor from the late 70s) is very, very slowly (one paycheck at a time) building a Nieuport biplane in his garage in Indiana. Last pictures I saw he had the frame for the body and tail connected and was getting started on the wings. Considering some of the less-than-brilliant stunts that particular QM2(SS) pulled in our glory days, I’m torn between rooting for him to get it airborne and dreading what will happen if he ever does.
But some of the comments about modern dual-mounts reminds… at one point I was offered a good deal on an “almost running” 1970s VW Thing (civilian Kubblewagon (sp?)) and was very tempting (despite considerable experience with good deals on cool vehicles that are “almost running”) due to the notion of buying right- and left-hand 12-gauge Remington 1100 semi-autos, fitting them with extended magazines and pistol grips, and welding up a dual pintle mount for the back seat of the Thing. Guess that would work for a replica biplane as well, should I find myself in another situation where I have more money than sense. (The norm is to have not very much of either….)
Hi, Jim :
Do you know if it’s a Nieuport 17 or an earlier version? Thanks in advance.
Really?! Mon Dieu,- my all time favourite single seater from WWI! Lets assume it is Model 17…. here is one for reference, in the air:
http://www.youtube.com/watch?v=GLpZET6_wxA
I believe it was also flown by American airmen along with SPADs – name Rieckenbaker is coming to mind.
So beautiful, so purposeful and yet so elegant and slender, like charming dancer…. oh MD!
While building replicas, the challenges are many and I am sure your mate is well into it. One major one is of course reliable engine. Some time ago I ran into page in which a German (I believe) small firm was offering original Oberursel, virtually identical to 9-cylinder rotary Gnome-Rhone. This is absolute must to see for every mechanics lover! And not to forget – to run it properly with all the right aroma and unavoidable ‘overspray’ you need genuine Castor oil!
“Biggles learns to fly” was the first book which I actually read right through, and it was the first book which I actually enjoyed reading.
I once met a former boat builder who had worked as one of the volounteers building the Shuttleworth collection’s Sopwith tri plane. Old T. O M. Sopwith took a very close interest in the project, and was so impressed with how closely the project had followed the original works drawings that he declared it to be “late production” rather than a reproduction, and awarded it a serial number. http://www.shuttleworth.org/shuttleworth-collection/aircraft-details.asp?ID=7
The reason for Bi and Tri plane layout was largely structural, the lattice girder fromed by the biplane structure is incredibly strong.
When Fokker was developing his “ein dekker” he had serious problems with wing spars breaking, they were strong enough in static loading tests with sand bags, but snapped in aerial testing. Official help from the air ministry boffins suggested strengthening the rear spar – which actually made things worse. Fokker then counter intuitively went to a lighter, more flexible rear spar which cured the problem sufficient for military use, however the plane still remained less structurally safe than its less aerodynamic biplane contemporaries. I gather that in the inter war period, several national governments banned monoplanes as inherently unsafe.
I’ve never flown in one of the WWi era designs, speaking to people who have, I’m told that they are absolute little [anatomical orifice of your choice]s for stalling and spinning with next to no warning,
and, the narrow (and usually un sprung)tail dragger undercarriage makes them particularly prone to ground loops on landing.
The radial rotary engines fascinated me for a lot of years.
That Albatross, with its in line engine and high exhaust, at least spared the crew from the constant mist of castor oil (hence they didn’t need a long scarves to wipe the oil off their goggles with – and it deprived them of an excuse for soiling their undies)
Up to the Bentley BR1 and BR2 rotaries with their aluminium cylinder jackets and pressed in cast iron cylinder liners, rotaries used a thin cup washer as the top piston ring, to accomodate distortion of the thin steel cylinder walls due to uneven heating and cooling. As a result, those rotaries required a full strip down and rebuild after every 8 to 12 hours of running.
Apart from the Gnome “Monosoupape” (single valve – it used the same cylinder head valve for exhaust and inlet, simillar to the inter war Guiberson radial diesel) all of the rotaries also had their crank cases full of explosive mixture – or hopefully explosive, as the air throttle and the fuel nozzle were controlled by different levers – when you opened the throttle, if you didn’t also open the fuel fast enough, the engine stopped firing, mixture had to be adjusted to where it started firing again, and then leaned off to where it ran smoothly.
The Gnome Monosoupape rotary was a constant speed engine, power could only be controlled by switching the ignition on and off, and relying on the momentum of the spinning prop and cylinders to start it again when the ignition was switched back on.
Add to all of those complications that it was well into WWi before a method of reliably recovering from spins began to be taught. The guy who worked it out, didn’t realize that no one else knew how to recover from a spin, and so for a long time, never thought to pass the information on.
Thanks for pitching in your part of knowledge Keith!
The issue of “aero-elasticity” as it had been know for some time was not known then. while attempting to make construction as rigid as possible, they were creating problem in opposite direction – making it fragile. Same applies for ships; I have seen once a video taken form bridge on rough sea and it was very visible how it was beautifully flexing. Without that ability it would probably break into pieces.
Speaking of engines; there is quite a bit of it to study and part of La Rome http://en.wikipedia.org/wiki/Le_Rh%C3%B4ne and oberursel there were also other German, British and Italian companies coming with their products. As usual, there is the dispute ‘who was the first’, but lets assume it was indeed La Rhone with its previous developments, as you write. I looked at comparative data of most commonly used La Rhone and Oberursel and found they are similar, but not the same. While output was comparable, the bore and stroke were not he same (with German engine having bigger bore and shorter stroke). As far as current replicas, the prime supplier seem to be Australian Rotec with their 2.8 litre 7-cylider radial (but not rotary) engines. They have substantially less displacement than WWI originals but they are economical and foolproof not to mention not creating oil mist.
Hi Denny,
The engineering history of ships, planes and road vehicles absolutely fascinating. There are a couple of books by the old prof of nautical engineering at Glasgow G.E. Gordon (“new science of strong materials” and “structures”)
They’re a great understandable introduction to those aspects of engineering and still interesting for people (like yourself) who already have a strong engineering background. I got the Fokker example from him.
Gordon did his degree between the wars, and said that the Griffiths theories of stress concentrators and crack propagation remained controversial and were not taught in naval architecture courses for many years, during which ships continued to snap in half (and they still do snap in half!)
He was also old enough and wise enough to be deeply sceptical of “new” materials, in one of his works he points out that (apart from its problems of warping and rot) spruce and balsa wood are superior for some aircraft uses to carbon fibre.
Your comments about bore and stroke differences between the Oberusal and La Rhone engines is very interesting, as the Oberusal began as a clone of the La Rhone.
Andrew Nahum, who is (or used to be) the curator of engines in the Science museum at London, produced an interesting little book on rotary radial engines http://www.amazon.com/Rotary-Aero-Engine-Andrew-Nahum/dp/0112904521
It was late 1990s when I got my copy direct from him (he kindly posted it to me without asking to be paid – I sent him a cheque in the next post, that kind of honesty and trust seems to engender great respect 🙂 )
His coverage of the last gasp of the radial rotary with the British and German efforts of going to 200 hp output with minimal gyroscopic effects is fascinating.
British bureaucrats had been led into putting hope in an unproven static radial, the ABC “Dragonfly” which spectacularly failed to deliver the hoped for performance and reliability (reports of cylinder heads glowing red during testing!).
As an emergency measure W O Bentley was been given the project to wring 200 HP out of a proven Clerget design, which he did by increasing capacity and by using conventional cast liners, aluminium pistons (very unconventional at that time) and succeded in producing 200hp with less gyroscopic effects than the parent 130 hp Clerget.
Apparently Bentley met considerable resistance and resentment at the factory he was posted to to undertake his work.
The Seimens Halske, sought to increase output by increasing revs but without increasing aerodynamic losses due to the spinning cylinders, or raising prop revs…
They achieved that by installing a differential gear at the back of the engine, so that the crank turned one way at around 1000 RPM, while the cylinders and prop rotated the other way at the same speed – clever fellows those Germans.
I wasn’t aware of the small Aussie static radial. I did see some of the work in progress in the early 1990s by a bunch of guys who were using air cooled cylinders and pistons, sourced from a 1970s Daf car, to make a small radial (I was between girlfriends at the time – they tend not to be sympathetic to me spending time (or money!) on such interests) I don’t know if the project ever came to anything, spouses, bank managers and day job employers all have a nasty habit of running out of patience before such projects are completed.
There seem to be some very nice inverted inline engines coming out of Czechia at the moment. They look like good material for authentic looking replacements for De Haviland Gypsy engines in Moths, Austers etc
Denny, it looks like Camden are selling copies of Lew Blackmore’s book on making a 1/4 scale working model of a Bentley BR2, at 1/10th the price amazon is asking.
they also have a youtube video of one of the completed 1/4 scale engines being started and flown
http://www.camdenmin.co.uk/collections/aero-engines/products/building-the-bentley-br2-world-war-1-rotary-aero-engine
Yes Keith, it is truly enjoyable to exchange ideas with you… and in more than one area!
You are also absolutely right about British pioneering efforts – they are not forgotten. As matter of fact The radial engines coming from your country between wars were likely on peak od state-of-art of the day.
Czech plane engine industry had its start start-up already during “First republic”. The Walter factory became quite proficient and their inverted six such as Walter Minor were mounted into Zlin/Trener line of sports aircrafts.
I will pursue the links you provided – thank you kindly Sir!
Thank you all, most kind and informative 🙂
See, we have quite a teamwork here; if one is lost another one steps in :=)))). I guess we are all lucky that way.
Very well said!
@ Earl Liew ref. Mar. 30th, 2014 @ 4;58 a.m. :
I should have said “The timing could not have been worse for the Allied air forces ( July 1915 )….”
Sorry for the redundancy.
Great slideshow ! Amazing how “techie” they were back then. My (German) great aunt showed me a picture of her grandfather – a well off farmer who served in WW 1 – I expected to see a well-dressed guy w.spiked helmet in a studio photo , but there he was – in a greatcoat with a big version of the WW2 helmet(the 1916) sitting in an old west style wagon sans canvas top..Looked for all the world like sergeant Schultz, used to take supplies forward in the morning and haul out the wounded(and perhaps the dead) on his way back…
What a great website : ) “Better get some work done, going home shortly he he”
RE: replica WWI aircraft.
Like the originals they tend to be difficult to fly. Part of it is that a well designed fighter (then as now) must be highly maneuverable, so maneuverability is weighted over stability.
The repros are either mostly accurate. (An example is Engels’s work, which Antony Fokker could only tell from his own by the higher quality and better finish) or they are eyeball accurate, with adjustments made in materials and design.
A good example of the latter type is Robert Baslee’s many replica kits, available at http://airdromeaeroplanes.com/. The “machine guns” are generally composite copies — very lightweight, and perfectly accurate if you don’t need them to shoot. There’s a shop in Pennsylvania that makes them.
@ Keith :
Your mention of Professor Gordon’s “The New Science Of Strong Materials” prompted me to pull out my old copy of that same book ( which I’ve kept since my college days ) and re-read it all over again. Ah, what memories — many thanks, my friend!
Gast in swedish museum: http://digitaltmuseum.se/011024404293/?query=gast&pos=10&count=21