Thread: Merlins

VH-AUB = Mustang
+ Spitfire

Bankstown around 1987
(Slide scan but not the best)



Martyn

Originally Posted by flagg

The Allison V1710 ran out of puff at higher density altitudes until they packed on the superchargers.. but by that time the Merlin was established.

.

Packed on Turbo chargers, they already had a single stage super charger. if you have a look at a lighting. Looking down at one of the fuselages’, 1\2 way down if the outlet exiting from the top, its a round thing, 2inches down is the turbo. The tips would glow red at night. they did try and fit it to the P40 but it took to long.

Originally Posted by flagg

Interesting.. I never knew that about the P38 variant, having only really followed the P51 which (intially) only had the single stage, single speed supercharger and didn't get the altitude performance until the Merlin variant - as you mention.

The turbo super charged Allison was around for a while but not used because it was not thought at the time that aviation would need to go so high for so long. another limiting factor was the over all length of the dam thing that engineering it into single seat fighters also required every thing else including the pilot to be moved back, a large job in its self as well as limiting the pilots view. None of these problems exists with the Lighting.

Originally Posted by isuzurover

Righto, Ben, what,where, who, when, and where did you find the photo?

Originally Posted by JDNSW

As a followup to Brian's last post - the Auster I used to own had a Gipsy Major III engine that was made by GMH in Adelaide. Another manufacturer of them during the war was, I believe, Tasmanian Railways. About 10,000 of these engines were made in Australia, the most of any aeroplane engine in Australia. Remember that at this time Australia did not have a motor manufacturing industry!

Australia in 1939 had the Wirraway in production, and was starting production of the Beaufort bomber, (including engines). In May 1942, the first Boomerang flew, fourteen weeks after the design was approved. Basically it was a beefed up Wirraway with a Beaufort engine. Although slow by contemporary standards, it was heavily armed and very manoeuvrable. In addition to these types, aircraft produced during the war included the DH82A Tiger Moth, Bristol Beaufighter and DH-98 Mosquito, with, as well as the Merlin and the Gipsy Major, several sizes of the P&W Wasp (Beaufort, Wirraway and Boomerang) and the Bristol Hercules (Beaufighter).

John

Cool the DH stuff i know very well. All the DH motors had metric threads with Imperial heads. Rather exspencive with the young air mechanics now days, worse is the 100hour re torqueing of wooden spar caps, you have to be there and watch them every second.

Originally Posted by JDNSW

As a followup to Brian's last post - the Auster I used to own had a Gipsy Major III engine that was made by GMH in Adelaide. Another manufacturer of them during the war was, I believe, Tasmanian Railways. About 10,000 of these engines were made in Australia, the most of any aeroplane engine in Australia. Remember that at this time Australia did not have a motor manufacturing industry!

John

GM-H made all sorts of odd things in WWII. Work boats, field guns, trailers among them.

The parent company's WWII output was prodigious. As well as the aircraft engines and components already mentioned they made complete aircraft, diesel engines, marine engines, locomotives, military vehicles, guns big and small, ammunition, tanks, armoured cars, furniture, civilian goods suitable for the military. Alfred Sloan states that GM then had 10% of the nation's metal manufacturing capacity, and that more than two thirds of their wartime production was products that were entirely new to them.

Chevrolet had not produced any of their own light metal components pre-war and by 1944 was the world's second largest maker of light metal forgings, and had turned part of their huge Detroit grey iron foundry into the world's largest producer of magnesium castings.

The Frigidaire Division was making civilian appliances for both the civilian market and the military, and making, lockers, cabinets, tables, chairs and so on from sheet metal for the military. They had unused capacity and asked the Procurements Board if there was anything in need that they could make. They ended up redesigning the Browning .50 machine gun so they could make it on their sheet metal machinery and by June 1945 had produced 328,000 of the short barrel version, in the process getting the cost down from $690 to $169 over three years. Other GM divisions were making the .30 machine gun and the M1 rifle.

Originally Posted by clean32

Cool the DH stuff i know very well. All the DH motors had metric threads with Imperial heads. Rather exspencive with the young air mechanics now days, worse is the 100hour re torqueing of wooden spar caps, you have to be there and watch them every second.

That is something I did not know about them (the threads I mean). I wonder if that is part of the heritage of those engines? As you may know, the first DH Moth used an Airdisco engine, which was made by mating four cylinders from a Renault V8 to a new crankcase. The Gipsy 1 engine was designed as a successor to this when the supply of disposal Renault engines ran out, so it is likely to have used metric threads as well, seeing the conversion and the Gipsy had the same designer, Major Frank Halford.

Of course you realise that small fasteners on the engines are certain to be BA - which has Whitworth heads but metric dimensions and threads (but a different thread form)?

John

Quick history, air motors

In the beginning there was every thing chain driven rubber bands but basically a pile of rubbish

Then some frog made it across the channel with out getting his feet wet.

Roll out the rotary mono valves, light easy to build Balanced
Then can the 6s and V12s both air and liquid cooled, 6 cylinder being the smoothest of all layouts but they all suffered with heavy flywheels in an effort to dampen down there vibrations. Damiler Benz, liberty etc

Next the radial came into favour, the 4 stroke giving now good power and didn’t suffer from the vibration problems of the inline motors. But they did have the problem of frontal area, in short more power = bigger motor= more drag

Next the V12s become popular again as they sorted out the vibrations and were able to produce more power with out melting things, but the down side was the same to much drag, they needed big radiators

Then came Glycol, effectively reducing the sixe of radiators to 1\3 of before. This gave the in lines a big boost, upping there power and size etc super chargers turbo chargers water and NOS injection etc.

Next came sodium filled valves and this got the radials back into the game and they started to play with super charges turbo chargers and water and NOS injection again.

Next came onboard radiators and the invention of the bleeding edge ( as can be seen on hurricanes and spits.) the first of the was the XP51, ( engineering wise it is this aircrafts only real claim to fame) this pushed the inline back in front of the radials.

There it about stops as in came the turbine