P-38 vs P-51
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MiTasol
1st Lieutenant
A REAL Beaufighter (like the vast majority of Brit aircraft) has the basic six as a separate panel among other things, and being British it is an ergonomic nightmare.
Unlike the Spitfire, Hurricane and many other British aircraft, the P-38 and P-51 (and Ki-45) did not require you to swap hands during takeoff (or landing) by putting the throttle/mixture/prop on one side and the flaps and/or landing gear controls on the other side. The Beau was like American aircraft in that the flap and landing gear were on the left. Most unBritish. The position of the trim controls was however very British - on the right so you had to swap hands to use them.
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WHile I appreciate people posting the pics of different cockpits of 2-engined aircraft, IMO that kinda misses the point. P-38 when compared with a P-51 had/has disadvantage in area of 'human interface'. In the 'America's hundred thousnad' it is remarked as with every new version, the cockpit controls and switches get more tedious to operate. Pilot of P-38J/L was to switch between up to 8 fuel tanks, vs. 6 for P-51D and up to 5 (usualy just 4 used) on P-47D; coupled with twice the number of engine controls that was supposed to make it harder to master, and easier for new pilots to make mistake when under pressure of imminent combat.
FLYBOYJ
"THE GREAT GAZOO"
And this human interface is overcome with TRAINING. 8 switches vs 6??? Sorry Tomo, this is a non-issue. If it's that mentally challenging for a pilot to activate a few extra switches, they shouldn't be flying airplanes!
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FLYBOYJ
"THE GREAT GAZOO"
How may times in the field were these adjusted????Sorry, but, as anyone who has worked on them will tell you, the P-38 is excessively complicated and it has nothing to do with having a second engine. It is so bad anyone would think it was British. Actually strike that - it makes British aircraft look quite simple.
This is a main landing gear door hinge - one of five per door so there are 20 per aircraft. What is not shown are the spring and the other casting. etc. Over 40 parts per hinge. The same basic design on the nose gear and gun bay doors.
View attachment 522250
Showing spring and some other details like the spools
View attachment 522252
Some detail off the technical drawing ("blueprint")
View attachment 522251
The main gear and door mechanism is also super-complicated with multiple cylinders (retract, uplock, downlock, door) pulleys, bell-cranks and cables. Lots of high maintenance items - especially when compared to the B-25 where one cylinder opens the main door, retracts the gear and closes both doors and once set up the mechanism is trouble free.
Gear
View attachment 522255
Doors
View attachment 522254
The P-38 was designed to fulfill a design spec and it was never envisioned that more than a handful would ever be built. Considering that almost 10,000 were eventually built and for a twin that had a pretty good MC rate (in the theaters whos' operators understood how to maintain and fly them) I think it's complexities were clearly overcome.
FLYBOYJ
"THE GREAT GAZOO"
Actually The P-38 is original. I believe that P-51 was rebuilt from a data plate
Shortround6
Major General
P-47s often operated with 3 tanks, Two fuselage and one belly but your point is taken.
The P-38 had two switches/selectors, basicly one for each side/engine although it was possible to cross feed. each selector switch (rotary) had a position for each tank plus cross feed for 5 positions. Granted that is a lot of combinations and you have two switches instead of one but they are right on top of each other and should be in the same position at the same time unless there are extraordinary circumstances. In combat the ideal position would be the main tanks and the selectors both set to upper left. Drop tanks (bottom) are gone and the reserve setting should not be being used unless bounced close to home field and all other tanks exhausted. Talking combat, obviously on a long fight it would be common to switch to reserve before landing.
The P-38 had two switches/selectors, basicly one for each side/engine although it was possible to cross feed. each selector switch (rotary) had a position for each tank plus cross feed for 5 positions. Granted that is a lot of combinations and you have two switches instead of one but they are right on top of each other and should be in the same position at the same time unless there are extraordinary circumstances. In combat the ideal position would be the main tanks and the selectors both set to upper left. Drop tanks (bottom) are gone and the reserve setting should not be being used unless bounced close to home field and all other tanks exhausted. Talking combat, obviously on a long fight it would be common to switch to reserve before landing.
soulezoo
Senior Airman
How wonky are those rudder pedals?
FLYBOYJ
"THE GREAT GAZOO"
Switching hands? So what!! I fly a GA single engine aircraft with a simple 160 hp engine and I switch hands all the time, continually trimming the aircraft, working the radios, GPS and looking at charts. Again, placement of switches and equipment in a cockpit is something you come proficient in during training while you're gaining familiarization with the aircraft.
IMO the complex P-38 cockpit argument is a myth created by Col. Rau who did not like the twin engine P-38, had many pilots ill-trained to fly them and were not operating them IAW the manufacturer's guidelines. If you think ETO P-38 drivers had it so bad, what about the 18 and 19 year old Bomber Command pilots flying Lancasters without co-pilots! I bet they were keeping busy if they had an engine out, especially during takeoff!!!!
IMO the complex P-38 cockpit argument is a myth created by Col. Rau who did not like the twin engine P-38, had many pilots ill-trained to fly them and were not operating them IAW the manufacturer's guidelines. If you think ETO P-38 drivers had it so bad, what about the 18 and 19 year old Bomber Command pilots flying Lancasters without co-pilots! I bet they were keeping busy if they had an engine out, especially during takeoff!!!!
MiTasol
1st Lieutenant
The need to switch hands is a failure in what is now called ergonomics at the design stage. No thought about the pilots work load at the most critical stages of flight which is take off and landing and where most accidents STILL take place, and probably always will.
Col Rau was not the only one having problems with not operating aircraft and engines IAW the manufacturer's guidelines. For a long while the whole USAAC/F refused to operate Allison engines IAW Allison's recommendations. As you say poor training was a significant failure.
Unlike the Spit and Hurricane the Lanc cockpit was quite well laid out but the pilot did have his hands full during ground ops because of the length of time between applying brakes and the air traveling at low pressure through small air lines from the control column to the air bags in the wheels and then inflating them. Nothing instantaneous like aircraft with hydraulic brakes.
Your comment comparing P-38 and the Lanc pilots work load is most appropriate - especially given the Lanc is a tail dragger and therefore prone to ground loop, especially if an outer fails before lift off.
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Hello Tomo Pauk,
One performance advantage of the P-38 that wasn't mentioned is its higher acceleration when compared to P-51 and P-47.
Some of those problems that you mentioned that were rectified really were not.
The Rate of Roll was improved with hydraulically boosted ailerons, but there was still a very bad lag until the beast reacted.
The permissible dive speed really did not improve at all. It was the ability to recover from a dive that was improved.
Nose tuck and loss of control still happened at the same speeds, but with the dive recovery flaps, there was at least a means of slowing down and pitching the aircraft up instead of just going for the ride.
The onset of Compressibility was at Mach 0.675 or about 450 MPH TAS at 30,000 feet.
Consider that this is only about 30 MPH above the maximum level speed at that altitude, so there really wasn't much margin.
Other odd things are that the fuel selectors in early and late models of the P-38 changed by quite a bit to the point where if you know how one works, it won't help you figure out the other one for cross feed.
The complexity of the P-38 cockpit was also a disadvantage according to pilot reports because it took a bit longer to go from cruise configuration to combat if bounced.
Personally, I believe the P-38 wins the beauty contest but of course that is subjective.
- Ivan.
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FLYBOYJ
"THE GREAT GAZOO"
The only thing complicated is you had to do the same process as you would do on a single engine fighter twice.
michael rauls
Tech Sergeant
- 1,679
- Jul 15, 2016
Ive read quotes from 3 or 4 p38 pilots that deploying the dive flaps before entering the dive to keep the plane under the speed of compresability in the first place was common practice. If this was the case and I would tend to believe the pilots that it was, the p38 from J25 on( wich is most of them) did indeed solve the compresability problem. Of course it was replaced with a slower dive problem but having your dive limited to say 470 mph at 25,000 feet isnt all that shaby. Alot of planes were starting to run into trouble not to far in excess of this anyway.
Hello Michael Rauls,
The placarded limits were 440 MPH @ 30,000 feet and 460 MPH @ 20,000 feet which corresponds to Mach 0.65 (from AHT).
Beyond that, there is gradual loss of control which sounds like a serious tactical limitation.
Is it a useful thing to be able to beat someone in a race to the ground and not have enough control to bring guns to bear?
I suppose it is useful if one is trying to escape.
My original point was really that the dive speed limitation really didn't get fixed at all. The dive speed limitation was there before and remained in place. With the dive recovery flaps, there was just a means of avoiding becoming a lawn dart.
- Ivan.
Shortround6
Major General
Manual says that the placard speeds could be exceeded by 20mph with the dive flaps deployed vs undeployed.
Not a great improvement. At low level it didn't really matter.
Not a great improvement. At low level it didn't really matter.
Hello FlyboyJ,
Here is an excerpt from a letter from 20th FG commander to 8th AF commander. Most of the contents sounds like just two of everything but some of it also seems to be a lack of ergonomics in the cockpit.
3. As a typical case to demonstrate my point, let us assume that we have a pilot fresh out of flying school with about a total of twenty-five hours in a P-38, starting out on a combat mission. He is on a deep ramrod, penetration and target support to maximum endurance. He is cruising along with his power set at maximum economy. He is pulling 31" Hg and 2100 RPM. He is auto lean and running on external tanks. His gun heater is off to relieve the load on his generator, which frequently gives out (under sustained heavy load). His sight is off to save burning out the bulb. His combat switch may or may not be on. Flying along in this condition, he suddenly gets "bounced", what to do flashes through his mind. He must turn, he must increase power and get rid of those external tanks and get on his main. So, he reaches down and turns two stiff, difficult gas switches {valves} to main - turns on his drop tank switches, presses his release button, puts the mixture to auto rich (two separate and clumsy operations), increases his RPM, increases his manifold pressure, turns on his gun heater switch (which he must feel for and cannot possibly see), turns on his combat switch and he is ready to fight. At this point, he has probably been shot down or he has done one of several things wrong. Most common error is to push the throttles wide open before increasing RPM. This causes detonation and subsequent engine failure. Or, he forgets to switch back to auto rich, and gets excessive cylinder head temperature with subsequent engine failure.
Hello Shortround6,
The first compressibility issue appears to be nose tuck and the nose up pitching moment of the dive flaps sounds like it is counteracting this. I wonder if this had any effect on buffeting that followed?
- Ivan.
CORSNING
Tech Sergeant
KiwiBiggles, check the mirror when you are 75 and let me know
what you think about wrinkles then.
what you think about wrinkles then.
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FLYBOYJ
"THE GREAT GAZOO"
This excerpt has been posted so many times I'm surprised no one is collecting royalties. This was from the Rau memo and paints an EXTREMELY exaggerated worse case scenario. So what made this soooo different from the same P-38 driver in the PTO??? Maybe the tropical weather made them think and react faster?!?!?
This is a myth - yea, if one got bounced in a P-38 it took longer to deal with the situation as you had 2 of everything, aside from that there was little differences in the process. Kind of funny though - if you look at a P-51 cockpit at the center pedestal there is a fuel selector valve. Look at a P-38 right side below the throttle - same valves, except there's TWO!!!
Then auto lean at 31" hg at 2100 RPM?!?!?
Here's a great story about the whole ETO fiasco - an expert from the article.
"Major General William Kepner, the fiery commanding general of VIII Fighter Command, wondered, as so many others did, why the P-38 wasn't producing the results everyone wanted, and what to do about it. Asked to provide a written report, 20th Fighter Group commander Colonel Harold J. Rau did so reluctantly and only because he was ordered to.
"After flying the P-38 for a little over one hundred hours on combat missions it is my belief that the airplane, as it stands now, is too complicated for the 'average' pilot," wrote Rau. "I want to put strong emphasis on the word 'average,' taking full consideration just how little combat training our pilots have before going on operational status."
http://www.historynet.com/p-38-flunked-europe.htm
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GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
The whole idea is to keep your eyes peeled so you (and your flight) don't get hard bounced.
And rookie pilots effed up in any ride, the P-38 didn't have a monopoly on that...
And rookie pilots effed up in any ride, the P-38 didn't have a monopoly on that...
wuzak
Captain
Wasn't the P-38's dive angle restricted because of the low Mcr and it accelerated well in a dive?
The dive flaps enabled steeper dives, but still not as steep as some of the single engine fighters.
