P-80 v Me 262 v Gloster Meteor....

[Shortround6]

the problem with the BMW motorcycle was that at the time they made three displacement engines. A 600, a 750 and a 900. All had the same stroke but had bigger diameter bores and pistons. There was one crankshaft which could only be counter weighted for one set/size of piston. While the 600/750 versions seemed to do fairly well ( I never owned one) the 900s vibrated at certain RPMs, This is not a manufacturing or quality control issue, it is an engineering/cost accounting issue. They tried to cheap out but any good engine man should have been able to tell them there would be problems even if they didn't know what kind. The end result was that the vibration traveled through the frame and caused the rear loop of the frame that passes around the rear of the fender and supports the rear of seat and tail lights to fatigue crack on the left side behind the shock absorber. First time ( cracked three times total) in under 8000 miles and the local mechanic started telling me where the crack was part way through the call. Not the first one he'd seen.

 

[renrich]

I agree that it is not fair to compare technology that is many years apart. One comparison though is valid. The 1982 928 cost about $ 50000 USDs in 1982. The 2006 Infiniti G35 coupe cost about $38000 USDs in 2006. If they had been making 928s in 2006 they would have been well over $100000 USDs. And, IMO, it would not be a better car than the Infiniti. Something is wrong here. One could observe that I was not very smart, buying those cars. They would be right!

 

[fastmongrel]

As someone who works for an independent garage specialising in Mercedes I might be a touch biased but I think Adler is right about Beemers. For all the reputation they are overpriced crap that is not a patch on lots of similar models across the range. For example if you want a 3 series Beemer you would be much better off buying a Ford Mondeo twice the car, much more reliable and much cheaper to run. Every time we get a beemer in the shop I am always surprised how cheaply made they are, underneath the shiny exterior they are a bodge particulary the wiring if you own a beemer and it develops an electrical fault sell it straight away before it incinerates you.

Its all about the badge if you want a good German car buy a Merc or a VW, buy an Audi if you dont mind everyone thinking your a dickhead or buy a Porsche if you just like spending money.

 

[DerAdlerIstGelandet]

I agree that it is not fair to compare technology that is many years apart. One comparison though is valid. The 1982 928 cost about $ 50000 USDs in 1982. The 2006 Infiniti G35 coupe cost about $38000 USDs in 2006. If they had been making 928s in 2006 they would have been well over $100000 USDs. And, IMO, it would not be a better car than the Infiniti. Something is wrong here. One could observe that I was not very smart, buying those cars. They would be right!

That is because you bought an import. Try buying an American "upper class" vehicle over here in Germany. For instance my Jeep Grand Cherokee cost $43,000 brand new in the United States, here in Germany it went for 58,000 euros (that is approx. 80,000 US dollars). Spare parts are very expensive for it here in Germany and if I take it to a shop it is extremely expensive.

I see so many young Americans over here buy brand new BMWs and Mercedes because they can afford them over here, then they get to the states and realize how expensive parts and maintenance is there.

As for the engine blowing up on the brand new Porsche on the way home, that can happen to any brand (it was probably built on a Monday ). A friend of mine over here ordered a brand new Ford Expedition, had it shipped over from the states to the base over here and on the way home the same thing happened.

I think we have gotten way off topic now though...

 

[Milosh]

I have a friend who is trying to restore a Bimmer 75. He is getting ulcers trying to get it to run properly. His biggest headache is the electrical system.

 

[renrich]

We are off topic but it was a 1972 MB 280SE 4.5, not a Porsche Brand new, white with red leather. I paid $10000 for it. They came and picked it up. I went to the dealership and they said we will repair it, give you another one or give you your money back. I said I was out of the notion for a MB so they gave me back my check. A year later I bought a 1973 MB 450SL for $12700. Three years later and 36000 miles the transmission was going out. Can't remember what I did exactly then but like a fool got another MB.

 

[drgondog]

I had the opposite experience with a 1977 MB 300TD that I drove 250,000 miles with one warranty covered turbo replaced and gearbox repaired at 210,000 - sold it for 3k in 2005. In between the second vehicle was a 1978 928 Porche that cost me about 25K in various repairs before we dumped that and started buying Suburbans.. 1995, then 2004 and stll driving the 2004 dogmobile (wolfhounds).

loved the looks and handling of that 928 more than any car I have ever had but it was a hanger queen.

 

[davparlr]

I had the opposite experience with a 1977 MB 300TD that I drove 250,000 miles with one warranty covered turbo replaced and gearbox repaired at 210,000 - sold it for 3k in 2005.

What do you expect from a taxi!

 

[davparlr]

Back to the original topic.

Like the F4U-4, the conflicting performance data on the P-80 is confusing, and commentaries on the P-80 referencing unavailable books and documents add to the confusion.

The comment that most confuses me is that the P-80 was tested against the Me-262 and was found wanting and so embarrassed the AF that the test results were withheld.

I bought "Arrow to the Future" by Walter J. Boyne and he indeed makes the statement that test were conducted by a Al Boyd and the test results were only recently found that showed the Me-262 "had better speed, rates of climb at different altitudes, and turning radius and that this data was "suppressed". He also referred a book "The Lockheed P-80", which I ordered and now have. That information surprised me in two ways. First, in 1946, military budgets were being decimated. Typically, today, the AF emphasizes it aircraft short comings in order to scare congress into more money to develop new fighters, the XP-86 was in the concept cycle at this time and may have benefited from a poor review of the P-80. Of course times do change and maybe the AF was concerned about cuts to the fighter program because of lack of performance.

The second issue I have is with other data I have on the P-80 that tends to contradict the possibility of such poor performance. The Me-262 may have out performed the P-80 but shouldn't have embarrassed it. First, the XP-80, which was a bit smaller than the XP-80A, was able to do 502 mph, or only 38 mph less than the Me-262 with 62% of the thrust of the Me-262. In addition the XP-80A, with 4000 lb thrust was able to do 553 mph. The P-80 design was definitely clean.

Data review of my own data, "Spitfireperformance", and other googled sites revealed several data source for the two planes. These are the data source I have found for the Me-262.

Spitfireperformance document on British test on German jet propelled aircraft. Although they claim to reflect performance of data provided by Germans, it has lower performance levels for the Me-262 and the thrust appears low.

German documents on speed of Me-262 with the Jumo 004B engine. This is the speed I will show although it appears faster airspeeds at lower levels than other sources.

Russian data that appears as just published data. I will show climb data from this site since it conforms to other sources.

Me-262 Pilot Debrief . German pilot Hans Fey who apparently flew acceptance test on the Me-262 and stated that minimum airspeed was 515 mph at some altitude below 13,000 ft., which is quite a bit below the airspeed stated in the German document above.

Arrow to the Future, a book on Me-262 by Walter J. Boyne which was a bit of a disappointment in performance data. What it did show was standard data points. It did show that the climb rate of the Me-262 was 3937 ft/min at SL.

This is the data source I have found for the P-80.

From Spitfireperformance:

3 December, 1946 test by AAF on airspeed comparison of production P-80A vs modified wing tips and nose. Document is signed by the afore mentioned Col. Albert Boyd. This aircraft was flown with the J-33-11 engine.

7 November, 1946 test by AAF on surface treatments. Document is signed by Col. Albert Boyd.

14 February, 1947, test by AAF on best, worst and average P-80A with J-33-9 engine
Document is signed by Col. Albert Boyd.

The P-80 Shooting Star, a book by E.T. Wooldridge, which shows a performance comparison of the P-80A versus the XP-84. While this data referenced an AF memorandum, I did not use this data. It showed a much higher speed than some of the other tests, including 562 mph at sea level.

So this is basically what I have.

Me-262 per German document for airspeed, common data for climb, and for the P-80A, with J-33-9/11 engines. The two P-80 engines were interchangeable and were rated at 3570 lbs thrust.
For airspeed, I made four comparisons based on spotty data. Me-262 (1) is worst case based on test pilot report that min airspeed was 515 mph and other airspeed estimates based on delta to best performance. Me-262 (2) is best case based on German data. For the P-80, (1) is worst case per test and (2) is best case.

Airspeed

SL
Me-262 (1) 515
P-80 (1) 520
Me-262 (2) 521
P-80 (2) 548

10k
Me-262 (1) 520
P-80 (1) 524
Me-262 (2) 531
P-80 (2) 544

20k
Me-262 (1) 529
P-80 (1) 523
Me-262 (2) 540
P-80 (2) 531

30k
Me-262 (1) 509
P-80 (1) 505
Me-262 (2) 518
P-80 (2) 510

40k
Me-262 (1) NA, above Me-262 ceiling
P-80 (1) 481
Me-262 (2) NA, above Me-262 ceiling
P-80 (2) 493

Climb

SL
Me-262 3960 ft/min
P-80 (1) 4300
P-80 4640

20k
Me-262 2160
P-80 (1) 2500
P-80 2830

30k
Me -262 1080
P-80 (1) 1650
P-80 1910

Ceiling
Me-262 37,560 ft
P-80 45,000

Looking at this data, the lowest performing P-80A is equivalent to the poorest performing Me-262 in airspeed and the best performing P-80A is equivalent to the best Me-262 in airspeed. In both cases, the P-80A is superior to the Me-262 in climb. It also must be noted that the P-80 has over a mile more ceiling than the Me-262. This, as demonstrated in Korea by the Mig-15, is a significant advantage.


In my opinion, the P-80A with specified performing of J-33-9/11 would be very competitive to the Me-262 in the fall of 1945, certainly to the extent that the P-80 would be produced in considerably more quantity than the Me-262. With the higher ceiling, the P-80 could exploit higher energy levels.

Why the disparity in the reported flight test pilots and the concern about the performance compared to the Me-262? Well, there may be a couple of reasons. One, which I think is the case, is that the engine performance of the early engines was erratic and difficult to measure, and that the P-80 used for reference just did not perform. This was a case in one of the test documents where an engine had to be replaced. Two, the Me-262 that was tested performed quite a bit better than all the referenced data.

It must be noted that I am not in possession of the flight test data of the AAF testing of the Me-262.

 

[FLYBOYJ]

Great post Dave! I believe its been mentioned that Chuck Yeager flew the Me 262 and he stated the performance of the P-80A and Me 262 "was about the same."