Battle stations. Did anyone watch it tonight????
Discussion
This is a first for me. (I think) an off topic post but its bugging me.
On channel 4's Battle Stations program tonight they were doing the potted history of the P-38 Lightning.
Charles Lindengburg (of atlantic crossing fame) flew with a Lightning squadron out in the pacific for a while. While he was there he suggested a modification to the plane that massivley improved its range.
Unfortunatley I went to the bog at this bit so I missed them saying exactly what the modification was.
Now it's annoying me.
How the hell did they massively increase the range with a simple engine tweak??
Andy
On channel 4's Battle Stations program tonight they were doing the potted history of the P-38 Lightning.
Charles Lindengburg (of atlantic crossing fame) flew with a Lightning squadron out in the pacific for a while. While he was there he suggested a modification to the plane that massivley improved its range.
Unfortunatley I went to the bog at this bit so I missed them saying exactly what the modification was.
Now it's annoying me.
How the hell did they massively increase the range with a simple engine tweak??
Andy
sadoksevoli said: Reducing the rpm and increasing the "mercury" - whatever that means - anyone else enlighten us/me?
The 'mercury' probably refers to the air pressure (those two puppies were supercharged) going into the engine, from that and the other comment the 'engineers' made I'd guess he was advocating leaning the engines right out.
What else could he do to double the range from 900nm to 1800nm?
Hmmmm.
So jack up the supercharger pressure, lean the engines riiiight out and reduce the engines rpm?
Presumably you'll also have to fiddle with the propeller pitch to enable the engines to run slower and the airplane to fly at the same speed.
I guess that fits. Pilots today still have control over their carbs and can lean engines out to improve range at the risk of melting valves etc etc.
Any pilots out there care to comment on the validity of this theory.
Andy
So jack up the supercharger pressure, lean the engines riiiight out and reduce the engines rpm?
Presumably you'll also have to fiddle with the propeller pitch to enable the engines to run slower and the airplane to fly at the same speed.
I guess that fits. Pilots today still have control over their carbs and can lean engines out to improve range at the risk of melting valves etc etc.
Any pilots out there care to comment on the validity of this theory.
Andy
I too missed the main part of this but I caught the bit where he said "drop to 3 inches of mercury" which is about 1.4psi, the engineers were saying it would burn the engines out. Hope that helps, another brilliant/beautiful design from Kelly Johnson.
I noticed the earlier jobs seemed to have different engines, was this another case of Allison to Rolls Royce?
I noticed the earlier jobs seemed to have different engines, was this another case of Allison to Rolls Royce?
hmmm
Don't see how dropping the charger pressure could burn the engines out.
Also I don't think the lightning ran merlins, I think it always ran the allison engine. Makes it one of the few V-12 engined planes during WW2 not to run the merlin. (I could be wrong about this though)
Where is eric when you need him...
Andy
Don't see how dropping the charger pressure could burn the engines out.
Also I don't think the lightning ran merlins, I think it always ran the allison engine. Makes it one of the few V-12 engined planes during WW2 not to run the merlin. (I could be wrong about this though)
Where is eric when you need him...
Andy
I was participating in my other "passion" - being a member of an operatic society (we're rehearsing "Chess" at the moment). I set the video on timer so hopefully I'll have something interesting to watch tomorrow night.
P-38s only used Allison V12s which were both supercharged AND turbocharged (although the early versions weren't turbocharged). The P-38 also could reach very high Mach numbers in a dive and a number were lost when pilots couldn't exercise enough elevator authority to pull the nose up at high subsonic speeds.
P-38s only used Allison V12s which were both supercharged AND turbocharged (although the early versions weren't turbocharged). The P-38 also could reach very high Mach numbers in a dive and a number were lost when pilots couldn't exercise enough elevator authority to pull the nose up at high subsonic speeds.
"In a pleasant manner Lindbergh explained cruise control techniques he had worked out for the Lightning's: reduce the standard 2,200 rpm to 1,600, set fuel mixtures to "auto-lean," and slightly increase manifold pressures. This, Lindbergh predicted, would stretch the Lightning's radius by 400 hundred miles, a nine-hour flight."
that'll be it then
that'll be it then
Niggle said: c/o google www.475thfghf.org/Lindbergh.htm
That doesn't look like a mustang
Amazing isn't it, that not flying at full throttle gives you greater range
H
HarryW said:
Niggle said: c/o google www.475thfghf.org/Lindbergh.htm
That doesn't look like a mustang
Amazing isn't it, that not flying at full throttle gives you greater range
H
I think the point was that the engineers and pilots all assumed that if you ran the engines this lean it would destroy them within the space of one mission. They'd underestimated the abuse the engines could take.
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