What would have been the best trainer aircraft for the P-38?

[XBe02Drvr]

Thanks, jgs238!
I'm kinda new here and ignorant of past threads. I see a lot of talk of torque in engine-out situations in that thread. What seems to be ignored is P-factor, a usually more significant influence than torque. In the sudden reduction of thrust and increase in drag from an engine failure, the resulting immediate increase in angle of attack causes an asymmetric thrust distribution from the propeller disc. The downward travelling blades have more angle of attack to their relative wind, thus generating more thrust than their upward traveling siblings. In the interest of controlability, you want that "extra" thrust to be as close to the aircraft centerline as possible. Compared to this effect, the effect of torque around an off-center mounted engine is relatively less. After years of multi-engine flying, mostly in aircraft roughly equivalent to a P-38 in size, weight and horsepower, (but not in testosterone!), I can vouch for the powerful effects of asymmetric thrust suddenly applied. A really brave (or foolish) check airman might even occasionally disable the autofeather circuit before pulling the power on one engine. Inside the marker on an ILS, the plane dirtied up and at or near Vref, that guarantees an exciting time! Still, simpler than it would be in a Lightning. No wonder we lost so many.

 

[FLYBOYJ]

Or neither, as no one engine was worse than the other! (semantics, I know, but you get what I mean)

I think that the left engine was considered 'critical' as there was only one generator?

On earlier models

 

[daveT]

"No wonder we lost so many"
number built Lockheed P-38 Lightning 10,037.
WWII flying safety took a back seat to combat. The AAF's worst accident rate was recorded by the A-36 Invader version of the P-51: a staggering 274 accidents per 100,000 flying hours. Next worst were the P-39 at 245, the P-40 at 188, and
the P-38 at 139. All were Allison powered.

 

[GrauGeist]

The A-36 was the Apache, the Douglas A-26 was the Invader.

As far as the Apache goes, it was used in a harsh environment, where ground attack was it's primary mission.

 

[jimh]

FlyboyJ is correct. Most insurance underwriters require a B-25 rating to fly the P-38 and F7F. It's not so much about critical engine but similarity of size, weight and ground handling.

Jim

 

[FLYBOYJ]

"No wonder we lost so many"
number built Lockheed P-38 Lightning 10,037.
WWII flying safety took a back seat to combat. The AAF's worst accident rate was recorded by the A-36 Invader version of the P-51: a staggering 274 accidents per 100,000 flying hours. Next worst were the P-39 at 245, the P-40 at 188, and
the P-38 at 139. All were Allison powered.

The fact that they were Allison powered had nothing to do with it. The P-40F had a Packard (Merlin)

 

[XBe02Drvr]

Interesting about those WWII accident statistics; did you notice the higher accident numbers were racked up by the relatively shorter legged aircraft that mostly logged less time per flight? Maybe accident rate per 10,000 sorties would be more instructive. What do you think? Is that something that can be resurrected from existing records? A statistian I'm not.

 

[gumbyk]

Interesting about those WWII accident statistics; did you notice the higher accident numbers were racked up by the relatively shorter legged aircraft that mostly logged less time per flight? Maybe accident rate per 10,000 sorties would be more instructive. What do you think? Is that something that can be resurrected from existing records? A statistian I'm not.

Makes sense - as far as accidents go, you are most likely to have an accident during take-off or landing.
I would guess that if you looked at accidents per sortie they would be about the same (maybe even less, as they weren't trying to land after an 8 hour+ mission). Just my thought though.

 

[daveT]

There is a huge data base of over 51,000 USAAF accident reports from about 1918 to 1956.
We are finding all kinds of interesting statistics using the data all the time.
for more about aircraft accidents see Wreckchasing Message Board

 

[GrauGeist]

Just to clarify, there were 500 A-36 Apaches built and put into service.

They were a formidable dive-bomber with a high rate of accuracy not to mention that they even accounted for 84 aerial kills. One Apache pilot even made ace.

So if we go over the list of 274 "accidents" per the MACR, I am willing to bet that it will include a great many losses incurred because of it's hostile operating environment.

The Germans hated it so much during it's operations in Italy, that they devised ways to stop it, such as stringing cables across narrow valleys and concentrating ground fire in "alleys" to try and stop it. This alone accounted for roughly 177 combat losses.

The A-36s assigned to the CBI, for example, had to contend with the KI-43 and higher altitudes where it was at a disadvantage, resulting in many combat losses.

 

[XBe02Drvr]

USAAF Never did buy Skyraiders; they were a Navy/Marine aircraft from the get-go. When the SAC-dominated USAF was forced to dirty their hands with such demeaning activities as Special Ops and COunter-INsurgency due to Vietnam, they had to pull retired Navy birds out of the boneyard and refurbish them for combat. In the high & fast world of the Zoomles, having Special Ops on your record could be a career-killer. It was a tarbaby.
The Skyraider wasn't the only bitter pill the Zoomies had to swallow. They set out to hold a design competition for a long range interceptor to replace the F-101, but SecDef McNamara intervened. "The plane you need already exists. It's called the Phantom, and the Navy's been flying it three years already. It works for them and it will work for you. BUY IT!" AARRGH!
Same thing happened when they reluctantly conceded they needed a high capacity (OMG!) SUBSONIC! attack jet. They were forced to swallow the Navy's A-7. Even in today's Air Force the stigma of low and slow is alive and well. They have tried repeatedly to ditch the Warthog despite its utility in the kind of wars we seem to be getting involved in these days.

PS: I don't know how this post wound up here. I posted it to the dive bomber thread and it duplicated here. WAY off topic. Apologies.
Wes

 

[XBe02Drvr]

"Please Mr. Secretary, you can't make us do this! It's heavy, it's awkward, it's UGLY, and it has a TAILHOOK, fer chrissake! It's got twomany pilots, twomany engines, and it's carrier-based thus inherently inferior to any land-based fighter!"
Just tell that to the families of the MiG and Sukhoi pilots it has shot down around the world.

 

[Zippythehog]

Piper Aerostar.

But they weren't built yet.

Zip

 

[XBe02Drvr]

Yuppper. Ideal multi-engine trainer. For those with a death wish. Forgiving?.......NOT!

 

[BiffF15]

Two seat P-38...

 

[drgondog]

Starting reading this wrong - very true, and engine out on take off killed a lot of butterbars.

Until SOP pointed out - a.) don't increase power immediately with good engine, and b.) don't feather (you may get the wrong engine - stabilize first and get a/c under control, then gradually apply power while getting clearance to go around and land.

The AT-9 was awful in S/E and was discarded early as transition

 

[drgondog]

Very true, the P-38 had TWO critical engines while the P-322 had just the one but the P-322 had less power as well.

As for the rotation direction (I read through the link) while inboard rotation provides the best single engine performance outboard rotation provides much better controllability at high power and high alpha as the propwash rotation gave the inboard wing the greatest angle of attack and the outboard wing the least. With inboard rotation, the throttles wide open and the wing at max alpha the wing section outboard of the nacelle is at first risk of stall, and it's very much more difficult to control an airplane with an outboard wing stall than inboard. In other words, they were going for best combat maneuverability not "oh-my-god-the-engine-might-quit" performance.

PS - As for the myth of the XP-82 not being able to fly with outboard rotation propellers due to the upward propwash being blanked by the wing on its way to the stab, the test pilot(s) simply tapped the brakes on takeoff roll to lift the tail. There are pictures of the XP-82 with outboard prop rotation in flight.

-->If Rambler still made cars I would own one, I suppose.<---

That wasn't the problem with first XP-82. The problem was upwash on center wing section increasing effective AoA to near stall - requiring the 'toe tap' to get the actual/combined AoA to Lift condition by forcing nose down. Changed the gears to opposite rotation and problem solved - with full elevator authority.

 

[XBe02Drvr]

a.) don't increase power immediately with good engine, and b.) don't feather (you may get the wrong engine - stabilize first and get a/c under control, then gradually apply power while getting clearance to go around and land.

All well and good if you have speed and altitude. If you're ten feet in the air, heavy, gear still down, TO flaps set, past V1 and VMC, but not yet to VYSE, you need all the power you can get and you need to wrestle the aircraft into its SE minimum drag/maximum lift flight attitude and STAY IN GROUND EFFECT until you reach VYSE. Otherwise you'll probably never accelerate or climb. If you can't meet these conditions, close the throttles, pull the firewall shutoffs, and brace for impact. Better to hit rightside up and slowing than inverted and accelerating.
VYSE and positive rate established, get the gear and flaps up, identify the dead engine CAREFULLY, feather and cage it. Hold VYSE and best SE attitude and run your engine out checklist. Best SE attitude for most twins is a very gentle bank into the working engine.
If you elect to take off from a field that doesn't give you ballanced field length under the ambient conditions, you're playing Russian roulette. For some perverse reason the same model of engine is statistically more likely to fail installed on a twin than on a single. My flying was just about evenly divided between singles and twins, and I never had a failure in a single, but two inflight shutdowns in twins.
Obviously if you're a Butterbar in a Lightning loaded for bear on a PSP airstrip on a jungle island, you don't have much choice in the matter.
Cheers,
Wes