Spitfire Question

[MorgothNL]

did they fix it in the mk II allready? I thought all merlins till at least the mark IV had the problem (IV is the first one with the griffon engine right ? )

[Skorteus]

Somehow I knew this would spawn an interesting conversation....you guys are fascinating to listen to.

[MorgothNL]

I did some research and found that indeed did the pilots could help the engine by inserting a piece of metal... but that didnt really fix it. because for this 'fix' to work..they HAD to dive at full power, wich was not always what they wanted. It was only in the last 100 series merlin that they put in a direct injection fuel pump .

The 60-85 variants also had a fuel pump...but this one did not have enough power. The 100 variant was using the crackshaft speed.

Now...I do not know wich spit had exactly wich variant of merlin .. but I think the mk2 was to early to benefit from the fuel pump variants


EDIT: this is what I found on wiki
the Merlin's lack of direct fuel injection meant that both Spitfires and Hurricanes were unable to pitch nose down into a steep dive. The contemporary Bf-109E, which had direct fuel injection, could "bunt" into a high-power dive to escape attack, leaving the pursuing aircraft behind because its fuel had been forced out of the carburettor's float chamber by the effects of negative g-force (g). RAF fighter pilots soon learned to "half-roll" their aircraft before diving to pursue their opponents.[25] "Miss Shilling's orifice",[nb 5] a holed diaphragm fitted across the float chambers, went some way towards curing the fuel starvation in a dive; however, at less than maximum power a "fuel rich" mixture still resulted. Another improvement was made by moving the fuel outlet from the bottom of the S.U. carburettor to exactly halfway up the side, which allowed the fuel to flow equally well under negative or positive g.[26]

Further improvements were introduced throughout the Merlin range: 1943 saw the introduction of a Bendix-Stromberg pressure carburettor that injected fuel at 5 pounds per square inch (0.34 bar) through a nozzle directly into the supercharger, and was fitted to Merlin 66, 70, 76, 77 and 85 variants. The final development, which was fitted to the 100-series Merlins, was an S.U. injection carburettor that injected fuel into the supercharger using a fuel pump driven as a function of crankshaft speed and engine pressures.[27]


still ... I dont know what aplies to wich spit

[Wissam24]

I've read that the F4U used to stall on the starboard wing before the port one at low speeds

[MorgothNL]

Originally Posted by Wissam24

I've read that the F4U used to stall on the starboard wing before the port one at low speeds

Yeah...I heard the same thing... but I could never figure out why this would happen . I can imagine it to happen at a go-around due to sudden torque effects... but I heard that the problem was mostly while landing on the carriers.
I understand that landing brings you close to stall speed...but why would one wing have this before the other one? prob because of the ugly looking wings

[Wissam24]

Originally Posted by MorgothNL

Yeah...I heard the same thing... but I could never figure out why this would happen . I can imagine it to happen at a go-around due to sudden torque effects... but I heard that the problem was mostly while landing on the carriers.
I understand that landing brings you close to stall speed...but why would one wing have this before the other one? prob because of the ugly looking wings

I asked a guy who did aeronautical engineering at uni how it was possible, and he didn't actually know.

[Skorteus]

I just learned another interesting fact about the Spitfire when it was converted for carrier use into the Seafire Mk47...in that because it was geared with a counter clockwise prop rotation (from the cockpit) that they had trouble during takeoff of hitting the flight control bridge to their right because of the opposite rudder control needed. I guess the new pilots were too used to right rudder, wow. Then came the counter rotating props to correct for this, damn, I learn something new every day. Thanks for the input all.

[Wissam24]

Please explain...

[MorgothNL]

Originally Posted by Skorteus

I just learned another interesting fact about the Spitfire when it was converted for carrier use into the Seafire Mk47...in that because it was geared with a counter clockwise prop rotation (from the cockpit) that they had trouble during takeoff of hitting the flight control bridge to their right because of the opposite rudder control needed. I guess the new pilots were too used to right rudder, wow. Then came the counter rotating props to correct for this, damn, I learn something new every day. Thanks for the input all.

I didnt quite get what you were saying... but I read a few times over ... and only then I saw you were talking about the seafire 47 ..
So you are saying... because the pilots were used to applying right rudder (because of the torque to the left)... the also used right rudder in the seafire 47 .. Even though the 47 was eliminating the torque effect with its 2 props . Thats ... well.. not hilarious... but still LOL

[Soviet Ace]

Originally Posted by MorgothNL

did they fix it in the mk II allready? I thought all merlins till at least the mark IV had the problem (IV is the first one with the griffon engine right ? )

That would be the MkXIV with the Griffon.

OH DAVID!!! WHERE ARE YOU!!?