Author Topic: A unique 'Stationary Engine' that never made it into the air(!!)....  (Read 947 times)

Offline xylstra

  • Jr. member
  • **
  • Posts: 3

  Hi, I wonder, may I call upon the long memories and contact books of the readership to help solve a mystery?    ...... and, the subject of my query?
             ..... The French MATHIS 'Vega' 42-cylinder (yes, you read that right!) liquid-cooled aero-engine. It was developed from the mid-1930's and two prototypes were completed and underwent testing. Somehow, amid the ensuing chaos of the German invasion, MATHIS personnel were successful in evacuating the prototype(s) {NB it is still unclear whether it was only one or both} to England and were gifted to the UK as a French contribution to winning the air-war and the ultimate liberation of France. The British Air ministry promptly responded by pinching their noses and replying "non merci!"
   The questions I seek answers to:-
 - How was the engine transported from France (what ship ]/ what aircraft [serial numbers]?   How was it transported to the port of embarkation?
 - What dangers, narrow escapes and tales were encountered on the journey?     Was co-operation provided by the British?
 - How many MATHIS personnel travelled with the cargo? - what were their names? - did they travel alone or did they bring their families? - what technical documents accompanied them?
 - What security arrangements were in place upon their arrival? Where was the engine(s) stored, indeed, exactlyhow many engines arrived? Where were the MATHIS personnel billeted?
 - Was the engine subjected to any dynamometer/test-house running? Was it air-tested? In what aircraft (serial numbers, pilot(s))?
 - Is there any surviving documentation relating to the engine, e.g. official memoranda, test reports, etc? Were technical blueprints and drawings archived? Where are they to be found now?
 - What finally happened to the engine(s): scrapped, or returned to France post-war (if the latter then where is it now)??
....... and what about the MATHIS personnel - did all return to France, did any stay on in England, what was their post-war career?
       ...... indeed, if they weren't working on the 'Vega' during the war, then what did they do?
  Due to the passage of time, first-hand eye-witnesses will no longer be around to tell the tale but I am hoping that perhaps, their descendants may have heard the stories or else be in possession of photographs, diaries, etc.
       I would appreciate all offerings of information and help.

Offline BillTodd

  • Full Member
  • ****
  • Posts: 426
  • Colchester UK (where the lathes were made)
    • Bill's website
I'm sure you're aware of this article but it may be of interest to others...

https://oldmachinepress.com/2018/12/05/mathis-vega-42-cylinder-aircraft-engine/
Bill
wy omnibus Latinis taurus stercore?

Offline Ian S C

  • Full Member
  • ****
  • Posts: 1063
  • Stirling Engine Maker Darfield Canterbury N Z
xylstra, I see that by Bill's link the engine was offered to the Americans not the English, as he went to the States to escape the Germans who he thought had a thing on him for miss deeds during WW1.
Ian S C

Offline Roger B

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3948
  • Switzerland
That would be a challenge to model  :)
Best regards

Roger

Offline steam guy willy

  • Full Member
  • ****
  • Posts: 2168
So.. Were there 6 banks of 7 cylinders ?  or 7 banks of 6 cylinders  interesting engine !!!!

willy

Offline Roger B

  • Global Moderator
  • Full Member
  • *****
  • Posts: 3948
  • Switzerland
7 banks of 6 cylinders. Radial engines apparently are better balanced with an odd number of banks.
Best regards

Roger

Online Vixen

  • Full Member
  • ****
  • Posts: 1222
  • Hampshire UK
A quick internet search reveals many references regarding the life history of Emile Mathis and the 42 cylinder Vera engine he designed. All references state he went to America for the duration of the war and later returned to his native France.

The concept of employing several banks of radial engine arranged in-line (one behind the other) was not unique to the Mathis Vega engine. In the UK, Armstrong Siddeley had been developing engines of similar configuration since 1934. Some of their notable in-line radial engines includes

The 37 litre Deerhound with 21 cylinders arranged as three rows of seven radial cylinders

The 61 litre Wolfhound with 28 cylinders arranged as four rows of seven radial cylinders

The 66 litre Boarhound with 27 cylinders arranged as three rows of nine radial cylinders

And the 94 litre Mastiff with 36 cylinders arranged as four rows of nine radial cylinders.

All these engines were dogs, in more senses than their names alone, none ever reached mass production. There did not seem any need for the 42 cylinder Vega.

Mike
« Last Edit: May 22, 2019, 08:29:40 PM by Vixen »
It is the journey that matters, not the destination

Offline Jasonb

  • Full Member
  • *****
  • Posts: 6519
  • Surrey, UK
All on your to do list Mike?  ;)

Online Vixen

  • Full Member
  • ****
  • Posts: 1222
  • Hampshire UK
Yes of course :lolb: :lolb:

Mike
It is the journey that matters, not the destination

Offline Bluechip

  • Full Member
  • ****
  • Posts: 798
  • Derbyshire

Offline steam guy willy

  • Full Member
  • ****
  • Posts: 2168
Re: A unique 'Stationary Engine' that never made it into the air(!!)....
« Reply #10 on: May 22, 2019, 11:38:04 PM »
what is the firing order of the vega engine and which cylinder do you start from ?? !!! and also all those other engines mentioned ?/

willy

Online Vixen

  • Full Member
  • ****
  • Posts: 1222
  • Hampshire UK
Re: A unique 'Stationary Engine' that never made it into the air(!!)....
« Reply #11 on: May 23, 2019, 05:12:11 PM »
what is the firing order of the vega engine and which cylinder do you start from ?? !!! and also all those other engines mentioned ?/

willy

Hi Willie,

 I will have a go at answering some of  your question.

The Vega had 42 cylinders (wow!!!) which were arranged as a seven cylinder radial engine repeated 6 times. All radial engines have the same cylinder firing sequence ie. they fire every other cylinder in sequence. So firing sequence of any seven cylinder radial engine will always be 1-3-5-7-2-4-6, That means every cylinder will fire once in two revolutions of the crank. This is a good solution which provides an even torque flow without many vibrational mode problems.

So that's how the first bank (bank A) of seven cylinders would have to fire. But the Vega had six such banks. There would have been countless permutations for the phasing of the different cylinder banks, but each bank would have needed to follow in the 1-3-5-7-2-4-6 sequence.  Some phase relationships between cylinder banks could have produced terrible longitudinal vibration problems, while others, less so. They did not have high powered computer analysis software in those days, so it may well have been a case of building the firing sequence to the designers best guess, then run the engine to see if it ran smoothly or if it wanted to shake itself apart.

You can begin to understand why most successful radial engines have similar configurations and why all of the odd balls fell by the wayside.

Mike

It is the journey that matters, not the destination

Offline BillTodd

  • Full Member
  • ****
  • Posts: 426
  • Colchester UK (where the lathes were made)
    • Bill's website
Re: A unique 'Stationary Engine' that never made it into the air(!!)....
« Reply #12 on: May 24, 2019, 09:34:44 AM »
logically, the 6 banks would have fired in a typical 6 inline sequence (given that this doesn't have the interleave , 'spiral', cylinders of an air cooled engine).
Bill
wy omnibus Latinis taurus stercore?

Online Vixen

  • Full Member
  • ****
  • Posts: 1222
  • Hampshire UK
Re: A unique 'Stationary Engine' that never made it into the air(!!)....
« Reply #13 on: May 24, 2019, 12:12:08 PM »
logically, the 6 banks would have fired in a typical 6 inline sequence (given that this doesn't have the interleave , 'spiral', cylinders of an air cooled engine).

Hello Bill,

I am sure you are correct.

A six cylinder in-line engine must fire all six cylinders in two revolutions of the crankshaft . Theoretically, there are 11 different firing orders to chose from, all of which will work. They all have one thing in common, the crankshaft throws are arranged in pairs at 120 degrees to each other. Each pair of cylinders fire on alternative crankshaft revolutions.

All radial engine also have a single throw crankshaft.

For the 42 cylinder Vega engine, all 42 cylinders must also fire in two revolutions of the crankshaft. It is therefore logical for two crankshaft throws (of the six banks of cylinders) to reach TDC simultaneously, two more banks arriving 120 degrees later and the remaining two banks at 240 degrees. Each pair of cylinder banks would fire on alternative crankshaft revolutions.

That configuration would satisfy all three requirements, A) to fire all 42 cylinders in two revolutions, B) each row of cylinders to fire in the standard radial engine firing order 1-3-5-7-2-4-6, C) all six cylinder banks of 7 cylinders to fire in one of the standard 6 in-line firing orders.

The engine would have a a very large number of identical components.  The cam shafts and ignition system would have been a nightmare to design, to manufacture and install on the engine to give the required ignition timing.

A big powerful engine but perhaps to clever for it's own good and too complex for survival.

Mike
It is the journey that matters, not the destination