the sexiest aircraft

"Bob Chilcoat" wrote in news:RxPyf.40$ snipped-for-privacy@fe12.lga:

There's also Kelly's British counterpart: Barnes Wallace.

Nope. The 'multibank' was a gasoline engine. Some Shermans DID have a Diesel engine though. These were the M4A2 model. These went to some of our allies (Russia), and the U.S. Marines used them, mostly in the Pacific. Being Diesels they were more forgiving of getting wet during amphibious operations.

Diesel tanks were also far less prone to 'brewing up' (catching fire) when hit, and were less likely to roast their own crews. However, their performance suffered compared to contemporary gasoline engined tanks. The Russins still had notable success with their WW-II Diesel powered tanks like the famous T-34 (often considered the best tank of the war).

In later years, as Diesels with better power to weight ratios were developed, the U.S. army switched to Diesel engines in their tanks. This occurred after the Korean war, about midway through the run of M-48 "Patton" tanks.

Nowadays almost all tanks are Diesel powered, with the notable exception of the turbine powered M1 "Abrams" tanks.

Dan Mitchell ============

Concorde - no question.

I saw the final flight of a Concorde into Filton (UK). As she landed a Spitfire overflew down the runway in a barrel role before climbing away. The two most beautifull aircraft in the sky together. The sadest thing was that Concorde will never fly again.

John

This is a well known "factoid" about diesel tanks, and the M4 Sherman in particular. However the evidence is that there's no difference in flamability between WW2 diesel and petrol tanks. Tanks of this period were rear-engined, had fuel tanks in the same compartment, and had rudimentary ammunition stowage. Where they burned, it was because ammunition propellant had been hit, not fuel. Most tanks for most of WW2 also carried solid shot AP ammunition, not HE, and so there was no explosive on board. A propellant fire will destroy the tank, but generally by a powerful fire rather than an explosion. Although tanks certainly burned, it was ammunition causing it, not fuel.

The Allies' safest tanks against this hazard were the late model M4A3 Shermans that switched to wet stowage of ammunition (incidentally,petrol fuelled).

In what way ? The US' diesel tank experiments were as a result of fitting the Guiberson radial diesel to the M3 light tank as a substitute for the Wright Continental W-670 radial. This was a perfectly satisfactory engine. It only caused problems when the Guiberson was then fitted to the far heavier M3 medium tank (1 1/2 times the weight of the light tanks, or the earlier M2 medium). This was an underpowered vehicle with the Wright engine too - the petrol version generally had the more powerful R-975.

The later diesels (the GM 6-71 twin diesel and the Caterpillar RD-1820) were comparable in power to the petrol engines, but had generally better torque characteristics and much better fuel consumption figures. The Caterpillar incidentally was only used in the M4A6 and just 75 of them were produced.

Neither the US nor the UK entered the war with a decent tank engine. The UK was using WW1 Liberty aero engines in the cruiser tanks (powerful, but infamously unreliable) and various twinned commercial truck or bus engines in the infantry tanks (very successful, but only suitable for smaller tanks). The US was dependent on radial aero engines (production needed for aircraft) and crash programs to twin commercial diesels. Not until mid-war did they really develop a dedicated tank engine, the superb British Meteor (a land-based Merlin) and the horrible Ford GAA V8. As always with US tank production, a pragmatic decision to facilitate production led to choosing a technically poor design, then producing it in overwhelming quantities.

In WW2 there was no performance penalty to using diesel engines in tanks. This was due to a simple factor - the poor quality of available petrol and its minimal octane rating. In comparison, wartime diesel suffered far less of a performance drop. The petrol Meteor could only achieve 1/2 the output of the very similar Merlin, due mainly to the relative qualities of "pool" petrol and Avgas.

This was the third mark of the M48. The M48A1 went to the M48A2 basically by supercharging the first petrol engine. Power was almost unchanged, but fuel consumption dropped to 2/3rd. The M48A3 switched to a turbo diesel engine (also used in the M60) to gain another 30% improvement.

Since the1960s it has been a bit of a misnomer to refer to "diesel" engines in tanks. The switch to compression ignition was driven by efficiency, but the fashion was also for multi-fueling (which really depends on using CI). There are CI and SI engines, but the fuel is a matter of availability.

Both UK and US engine fleets are now free of petrol engines and are purely diesel. Only motorbikes, chainsaws and some US generators still require petrol - the UK replaced its generators a few years ago and both are still searching for a workable diesel motorbike.

The Abrams gas turbine was also developed as a multi-fuel engine, which commonly burns diesel. Jet A-1 is perhaps the "ideal" fuel, but has little difference from DERV (vehicle diesel) - equally a Challenger will happily run on jet fuel. Early Abrams models could burn petrol too (badly - this is hard for a gas turbine) but I understand that this facility is no longer used.

The old girl looks a bit anorexic next to a Vulcan though :-)

Mark Rand RTFM

I nominate the B58 Hustler if no one else has. In love since with her since day 1.

wws

Four-stroke radial engines have to have an odd number of cylinders per row in order for the firing order to work (i.e. 1,3,5,7,2,4,6 for a seven-cylinder configuration). The only radial engines with even numbers of cylinders are 2-strokes. There may be some oddball exceptions, but I'm not aware of any.

Barnes Wallace had a great career, but he wasn't an aircraft designer. His bouncing bombs and earthquake bombs were both big successes, but I don't believe he ever designed an airplane. R. J Mitchell, however, WAS a great aircraft designer. His Schneider Trophy planes were beautiful, and led directly to the Spitfire.

So does this apply to multiple row radial engines, too?

Tom

I'm looking now at an aluminium Mosquito that my late uncle filed up from scratch in between servicing Merlins for Halifax bombers in 624 squadron. Beautiful! ----------------------------------------------------------- snipped-for-privacy@boltblue.com

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Try the Wellington and the Wellesley (among others).

He was Vickers' chief aircraft designer at the time.

Sorry, I stand corrected. I read his biography years ago, but didn't recall any association with Vickers.

BTW, for those of you who are Mosquito and Spitfire fans, have a look at this:

(warning - large file). When I first saw this, I thought, wow, there are FOUR airworthy Mosquitos somewhere. I then went back to the original link and saw that these are computer generated! Completely fooled me. The story on this video simulation is at: . Pretty amazing.

For multiple rows you can do it either way, although balance might get odd for some combinations.

After all, a H4 is just a two-row two-bank radial.

Bob,

You might want to re-read Paul Brickhill's "The Dam Busters" also.

His bomb work was only a part-time effort, undertaken during lunch breaks and in his "off time".

In addition to the Wellington and the Wellesley bombers of WW2, you may be more familiar with 2 of his later designs: the Harrier and the Concords.

I re-read it about ten years ago. Still a good read. I read it the first time in the 60's (damn, giving away my age again).

I last re-read it last week (for the umpteenth time).

Don't worry about the Vintage Factor: I still remember the Blue Angels performing in F6Fs at the Corpus Christi NAS Airshow. [I wound up with a terrific sunburn that day.]

Didn't have something to do with the Wellington bomber?