MOST OVERRATED AIRCRAFT OF WWII

[tomo pauk]

Thank you for setting my numbers right, folks

Problem for the P-38 in "classic" layout is that once you stick on the turbos and stick the radiators way back you have really long nacelles anyway. Please remember that they did sketch out many alternatives.
...

I'd stick the radiator in the front of the nacelle. That also saves weight for the cooling system. Add the saved weight from going on with classic layout, along with now lighter U/C that can be used means smaller and thinner wing can be used, for the same wing loading and better speed.
Better yet, stick the proper intercoolers in the nose, burry the radiators in the outer wing section, like at Airacuda.
Plenty of space in the fuselage for fuel now.

 

[LisaM]

...., while Do 335 used 'legacy' engines for same turn of speed.

As a what-if, too bad Dornier did not went out earlier with such a concept, employing two Jumo 211 or DB 601/605 engines.
.

Hornet used 130/131 Merlins, a further development of the well used 113, hardly radical. The big changes were the single point fuel injection aliowing 20lb boost on 100/130 octane (better metering) whoch was downdraught allowing a closer fitting cowling) and a more radical cam (in fact the only Merlin wih a different camshaft profile).
Despite giving away 17 litres about the same power as a DB-603A when on 100/130 fuel and a lot smaller and lighter

The most most commonly quoted DO-335 performance was 426mph without WM-50, 474 with..21.000lb vs 16,.000lb so guess what is going to;climb faster (and the Hornet had the lift affect of airflow from the props over the wings). So the Hornet was as fast,, climbed much better and was more agile (44lbs per sq wing loadibg vs 51lbs)..

A Do-335 with a DB-605? Roughly 200bhp lower power (with or wthout MW-50) puts its performance in the 450/400 class (with or wthout MW-50) Not particularly radical for late '44. A big plane like that would have been a nice target at altitude for the Mustangs and Spit XIVs of the time. And if MW-40 wasn't available (common) or if it ran out it would have been a dog.

And there were still serious development issues like overheating in the rear engine to overcome.

DH threw the Hornet together in about a year from mock up (Sea Hornet took a bit longer) and it was near pefect out of the box. The prototypes were puling 490mph, dropping to 475mph in service condition.

So there was no real comparison DH took the sensible engineering approach building on their Mosquito and Vampire (also in development) experience using a further development of the tried and tested Merlin. Dornier went down a daft route, over focusssed on one issue (that could be dealt wth in other ways , the Ta-154 did as well) and created a lot of whole new problems for themselves, compromised other performance elements (like climb) as well as making the whole thing rediculously complex and tied themseves to that other disaster the DB-603. Hardly an uber plane.

 

[tomo pauk]

The Merlin 130 series were from 1945, the BD 603A was from late 1942, so yes the Hornet used the engine that was one, if not two generations ahead. Hence far better power despite smaller weight and bulk.The term 'single point injection' is a better looking name for 'injection carburetors'?
It were strengthenings of the engine that enabled +20 psig boost on 130 grade fuel, not the fuel metering.

I'm not suggesting Do 335 with DB 601/605, but a fighter similar to the Do 335 with plain vanilla engines. So 300 sq ft wing instead of ~400 sq ft, 6 tons instead of 7.5 (empty), 12 meters length instead ~14.

Developmnet of the Hornet was indeed fast, there was Mosquito, Whirlwind and Welkin to see what can go and what need to be avoided. Neither P-38's nor Do 335's designers posessed such luxury. The Do 335 was no more complex than P-38, nor it's development looked like a protracted thing

 

[DerAdlerIstGelandet]

I'll come back to the P38 later,but I always see the Do-335 as one of those ideas you have with workmates over too many drinks on a Friday...then you come back sober on Monday and then realise how stupid it was.

The probem was to 'solve'a prpblem (drag) it made a whole new bunch of other complex problems The contemporary DH Hornet was just as fast (475mph, 490 in some tests, and outclimbed a Spt XIV. 1,500 miie range on internal fuel) was superior in every other way and it was a conventional twin design. Just that DH paid careful attemtion to reducing drag where it mattered, the end result was a plane with astonishing performance, easier to make (maintain, etc) and almost certainly cheaper as well.

There is nothing stupid about the design. Interresting and complex, but not stupid.

Sure it had it's design flaws, and problems, but what new aircraft does not?

I think it was a waste of resources, but the design worked.

 

[FLYBOYJ]

Lisa, still waiting on your perceived "quality issues" with the P-38. So far you've shown little to support your rant.

 

[Shortround6]

Thank you for setting my numbers right, folks



I'd stick the radiator in the front of the nacelle. That also saves weight for the cooling system. Add the saved weight from going on with classic layout, along with now lighter U/C that can be used means smaller and thinner wing can be used, for the same wing loading and better speed.
Better yet, stick the proper intercoolers in the nose, burry the radiators in the outer wing section, like at Airacuda.
Plenty of space in the fuselage for fuel now.

You are using present day knowledge as to the smaller and thinner wing. Only difference in weight for the cooling system is the weight of the pipes going back and forth.
Not sure about the weight saving of the classic layout, several hundred pounds or 50lbs?
Gee, you might have saved enough to clip 2 sq ft from each wing
When the P-38 was first designed those "proper" intercoolers may not have existed ( the one in the P-39 was certainly a dog's breakfast) and the B-17 had more volume to put things than they knew what to do with.

And pick what you want and stick with it.

It is easy to bury radiators in a wing when the wing is almost thick enough for a man to crawl though. Airacuda had tunnels through the inner sections of the wing between the nacelles and Fuselage.
You can get a wing that will easily hold radiators AND be thin if you use a wing bigger than the one on a B-25

 

[tomo pauk]

The knowledge that lower weight means smaller wing was present before ww1. Smaller wing can be thinner in absolute terms, if not in percentage.
Weight of fuselage:
Hornet: 561 lbs + nacelles of 141 lbs = 702 lbs (link); same for Sea Hornet
P-38 (pod, booms): 1454 + engine section 471 lbs = 1925 lbs

Less weight away from centreline, along with smaller wing also means improvement in rate of roll, no booms means less blind spots for the pilot. A bit smaller A/C, of non-distinctive shape, means that enemy pilots will need to come in closer to judge what is trying to do that aircraft over there.
The Whirlwind managed with burried radiators despite the wing of smaller profile, granted the 'P-38' will need bigger radiators, but it will also have bigger wings.

 

[stona]

I'm currently building a model of the Do 335 M13 (prototype for the B-2 zerstorer). Whilst I agree that there were problems with the design it can't be described as stupid or absurd. It would have made a formidable aircraft with 3 x 30mm and 2 x 20mm cannon.
Here's where I'm at, showing the extended wing.

The most over rate aircraft of WW2 that actually saw significant service......the Me 262.

Cheers

Steve

 

[GrauGeist]

I am still not sure how the P-38 can be "over rated"...it provided a great deal of contributions in all theaters during the war, including high-speed PRU.

It never reached "legendary" status like the P-51, Spitfire or Bf109 and if it were removed from the historical timeline, would have left quite a vacuum.

Two very famous people who's lives were directly affected by the P-38: Admiral Yamamoto and Antoine de Saint Exupery.
This of course, doesn't include the number of enemy A/C downed or targets eliminated by it.

If we want to go by sentiment, then I would suggest the A6M was a little "over rated", as everyone was referring to Japanese fighters encountered, as a "Zero" when it was often times other types and it was not as invincible as it was made out to be.

 

[Shortround6]

The knowledge that lower weight means smaller wing was present before ww1. Smaller wing can be thinner in absolute terms, if not in percentage.
Weight of fuselage:
Hornet: 561 lbs + nacelles of 141 lbs = 702 lbs (link); same for Sea Hornet
P-38 (pod, booms): 1454 + engine section 471 lbs = 1925 lbs

Less weight away from centreline, along with smaller wing also means improvement in rate of roll, no booms means less blind spots for the pilot. A bit smaller A/C, of non-distinctive shape, means that enemy pilots will need to come in closer to judge what is trying to do that aircraft over there.
The Whirlwind managed with burried radiators despite the wing of smaller profile, granted the 'P-38' will need bigger radiators, but it will also have bigger wings.

Lockheed as a company had built 3 different twin engine all metal monoplane airliners before working on the P-38 and was working on an extended fuselage version of the last one at about the same time as the P-38. One has to figure that Lockheed as a company (even if not individual designers) had a pretty fair idea of what conventional fuselages would weigh compared to the pod and boom arrangement. Hornet was designed about 5-6 years after the P-38 and incorporated a lot that had been learned in the mean time. It even used a lot that had been learned since the Mosquito was NOT simply a skinny fuselage Mosquito. The Hornet also needed a bit of a learning curve as they found that using props that rotated the same as the P-38s but found that this blanked the fin and rudder and affected low speed control so the engines were swapped and Hornet props rotate inward at the top of their arc.
This was flying 6 years before the P-38 and was considered pretty "hot stuff" in 1931-32.

Most twins are going to have a distinctive shape compared to single engine fighters.

Maybe you can put the radiators in the wing roots. Now you have to put the fuel (or most of it) in the fuselage and it either has to go on the center of gravity (cockpit way forward or way aft) or sandwich the cockpit with fore and aft tanks and have the pilot switch back forth to maintain trim. P-38 pilots had to do that any way with the four wing tanks. Also please note that P-38 eventually wound up with engines that needed almost twice the cooling capability as the Whirlwinds engines. Might not want to make the wings too small or too thin if that is where the radiators are going.

 

[tomo pauk]

Curiously enough, Hornet's wing was heavier than of the P-38s, it was also a little bigger but of thinner profile. The wood is not carbon fibre, expecting that DH gained so much expertise that they will just on that account be able to cut structural weight by 60% is far fetched to me.
'Alternative P-38' will still have a 20% bigger and maybe 25% thicker wing than Whirly. Poor pilots were messing with 6-8 fuel tanks in the P-38, hopefully we could cut this down number by one.
Lockheed never produced a twin boom aircaft prior P-38?

 

[FLYBOYJ]

Poor pilots were messing with 6-8 fuel tanks in the P-38, hopefully we could cut this down number by one.

Please explain?!?!

 

[FLYBOYJ]

Later model P-38s had either a four or five way fuel selector that included a crossfeed detent. This was no more complicated than other twin or multi engine aircraft of the period, in fact similar fuel selectors can be found on many aircraft built in the post war period and even today.

 

[tomo pauk]

Please explain?!?!

My proposal, or what was historically fitted?

Anyway - historical start was with 4 tanks, two at each inner wing, thier places separated with main spar. Two drop tanks added. Two leading edge tanks, each 55 gals, were added with change of intercooler type and location. Makes for total of 8 tanks.

Having the 'classic' fuselage should allow for some decent fuel tank there, whether with 100, or 150, or maybe 200 gals, so there is no need for LE fuel tanks, hence 1 fuel tank less.

 

[GrauGeist]

Lockheed never produced a twin boom aircaft prior P-38?

No, the P-38 was Lockheed's first "twin-boom" airframe. They did have two other projects that fell along the P-38's configuration: XP-49 and XP-58, only one airframe of each type were built.

Keep in mind that Lockheed did have a great deal of success with their prewar twin engine types, the Electra being the most widely recognized.

 

[FLYBOYJ]

My proposal, or what was historically fitted?

Anyway - historical start was with 4 tanks, two at each inner wing, thier places separated with main spar. Two drop tanks added. Two leading edge tanks, each 55 gals, were added with change of intercooler type and location. Makes for total of 8 tanks.

Having the 'classic' fuselage should allow for some decent fuel tank there, whether with 100, or 150, or maybe 200 gals, so there is no need for LE fuel tanks, hence 1 fuel tank less.

The fact that there were 8 tanks had little to do with the pilot. He managed the Reserve, Mains, drop tanks and when necessary, crossfeed.

All good providing you could accomplish this structurally. One of the reasons why you have multi fuel tanks is because the fuel system is built around the structure - during design the usual "pecking order" is aerodynamics, structure and then systems. I've seen engineers of the 3 disciplines want to choke each other at times.

 

[FLYBOYJ]

The P-38's twin boom design was an answer to an engineering problem that would satisfy the AAC specification that led to the P-38 development.

 

[tomo pauk]

The fact that there were 8 tanks had little to do with the pilot. He managed the Reserve, Mains, drop tanks and when necessary, crossfeed.

All good providing you could accomplish this structurally. One of the reasons why you have multi fuel tanks is because the fuel system is built around the structure - during design the usual "pecking order" is aerodynamics, structure and then systems. I've seen engineers of the 3 disciplines want to choke each other at times.

No problems with later paragraph.
We know that even the tiny fuselage of Bf 109 managed to have installed a bit over 100 gals of fuel, plus the extra MW-50 tank.

As for the 1st paragraph, you may note that pilot was using two 4-way switches in pre-J models of P-38, or two 5-way switches in P-38J and -L. Child's play for a seasoned 'twin' pilot, a real hassle for a pilot fresh from flying shcool, with few hours of conversion to P-38, as noted by Col. Rau's letter.

The P-38's twin boom design was an answer to an engineering problem that would satisfy the AAC specification that led to the P-38 development.

99.9% of aircraft were a response to requirement. While I like P-38, I don't regard it as holy cow, any more than other aircraft.

 

[FLYBOYJ]

No problems with later paragraph.
We know that even the tiny fuselage of Bf 109 managed to have installed a bit over 100 gals of fuel, plus the extra MW-50 tank.

True, but I guarantee you the size and location of the fuel tanks (as well as the MW50 tank) was dictated by the structure

As for the 1st paragraph, you may note that pilot was using two 4-way switches in pre-J models of P-38, or two 5-way switches in P-38J and -L. Child's play for a seasoned 'twin' pilot, a real hassle for a pilot fresh from flying shcool, with few hours of conversion to P-38, as noted by Col. Rau's letter.

All true and that's why flying the P-38 (or any high performance twin) was a different breed and required a lot more training then the AAC initially gave. Many of the more successful P-38 drivers checked out in the B-25 or A-20 to gain twin experience. Rau's letter condemnation of the P-38 was seen as an across the board assessment by many, when in fact it should be looked upon as a major flaw in AAF training. Even his critique of instrument and switch placement was arguable as the P-38s cockpit arrangement was comparable to many twins of the period. Bottom line, he (and many others) didn't like flying twin engine aircraft, especially in combat!

99.9% of aircraft were a response to requirement. While I like P-38, I don't regard it as holy cow, any more than other aircraft.

True, but what makes the P-38 unique was the way Lockheed approached the engineering problem - an aircraft that flew 400 mph when the Biplane was still considered contemporary.

 

[FLYBOYJ]

Oh - and let's not forget - despite it's accolades and flaws, triumphs and fails, it was never intended to build more than 75 P-38s, the only US fighter in production before the start of the war and to remain in production till the end.