XP72 "superthunderbolt" vs TA152 How would they stack up?

[tomo pauk]

Hi, jim,

5) Ta 152 s mechanicaly driven supercharger was faster reacting during dogfights than turbos .

XP-72 did not have a turbo.
The speed of reaction of turbo was not an issue in P-47, nor in P-38, the main fighters using turbo. The speed of the propeller's reaction is what reduces abrupt RPM changes anyway, since the prop acts like a flywheel (see SR6s posts).

 

[Siegfried]

A turbo-compound R-4360 was some way into the future at the end of WW2.

Test pilot Tom Bellinger stated flatly that the no flights ever exceeded 500 mph. The dash 13 engine was not supercharged. With the planned but never installed dash 19 engine (with a remote supercharger) rated at 3,650 HP at 25,000 ft. (3,000 HP at sea level) a top speed of 504 mph at approximately 25,000 feet was expected. Planned further development of the dash 19 engine was expected to yield approx 4,000 hp and a speed of 540 mph at 25,000 ft.

Hence we are comparing a XP-72, which achieved 480mph in level flight during its test program with a Ta 152 which achieved 472 mph also in test but also achieved production and service. The key difference is service ceiling with the Ta 152 likely higher due to its high aspect ratio wings.

It is possible to project advanced production versions of the P-72 which are faster (490, 500 or 540) but wouldn't one expect that the Ta 152H would also have been improved considerably in that time frame?

 

[wuzak]

Test pilot Tom Bellinger stated flatly that the no flights ever exceeded 500 mph. The dash 13 engine was not supercharged. With the planned but never installed dash 19 engine (with a remote supercharger) rated at 3,650 HP at 25,000 ft. (3,000 HP at sea level) a top speed of 504 mph at approximately 25,000 feet was expected. Planned further development of the dash 19 engine was expected to yield approx 4,000 hp and a speed of 540 mph at 25,000 ft.

Hence we are comparing a XP-72, which achieved 480mph in level flight during its test program with a Ta 152 which achieved 472 mph also in test but also achieved production and service. The key difference is service ceiling with the Ta 152 likely higher due to its high aspect ratio wings.

It is possible to project advanced production versions of the P-72 which are faster (490, 500 or 540) but wouldn't one expect that the Ta 152H would also have been improved considerably in that time frame?

The R-4360 was supercharged regardless of whether or not the remote auxiliary supercharger was fitted. If the remote supercharger was not fitted to the prototype (I do not know either way) the R-4360 was simply a single stage supercharged engine, with an integral supercharger.

The only R-4360s, to my knowledge, that weren't fitted with superchargers were the VDT versions - which ran on the test stand and flew in a B-50 (post war) but required the constant attention of the flight engineer to prevent the turbos from overspeeding. Some VDT schemes were turbocompounded, others not.

 

[GregP]

Hi Jim,

I do all my performance calculations (wing loading, sp[an loading, pwoer loading) at Normal Takeoff Weight, not Max Weight. You are free to do whatever you want, though you SHOULD do it the same for both aircraft. In reality, the combat weight are less than normal takeoff weight becasue the fighters burned fuel getting into position for combat, drop any extra tanks, and usually drop underwing bombs, too, if engaging in aerial combat. So, my numbers are conservative, as best practice dictates.

My database shows the XP-72 with a normal takeoff weight of 7,940 kg and a rated power of 2,573 kW, for a weight to power ratio of 3.1 kg / kW. I show the Ta-152H at normal takeoff weight of 5,219 kg and a rated power of 1,305 kW, for a weight to power ratio of 3.4 kg / kW. Advantage XP-72. Not by a lot, but an advantage nevertheless. The Ta-152H wing was optimized for high altitude, not for dogfighting. A high-altitude wing is not necessarily a great climbing wing. What it does best is maintain lift over a wide range of air pressure values better than less specialized wings.

The XP-72 had a Pratt Whitney R-4360. I don't know the XP-72 airfoil, but the P-47N was pretty good at high altitude ... one of the best of the war in real life. The main reason the radial-powered aircraft cruised rather slowly in most cases was range. They have no problem cruising faster, but eat fuel doing it. Almost ALL fighter warbirds today cruise at 225 - 240 knots, not due to book or to fuel consumption, but due to the speed limit below 10,000 feet in most coutries.

I dispute your claim number 2 above. Prove it. The Ta-152 wing is probably better at high altitude, above 40,000 feet, at producing lift. There is no evidence it was better at dogfighting. If the Ta-152 pilot "yanked and banked" and lost speed, he was out of the best envelope for his specialized high-altitude wing and probably stalled.

As for top speed, my quick search says 503 mph for the XP-72, as do several of my references, so it stands with me as OK.

The title of this thread says Superthunderbolt vs. Ta-152; it never mentions timeline. In my opinion, the Ta-152's used were service prototypes (the Ta-152H first flew in 1945, later than the XP-72) and made NO difference in the war. They were ALMOST in service, but not really, with never more than 25 in operational units, the mechanics didn't even get enough training. The entire fleet accumulated only about 50 flying hours befire being thrown into combat. By war's end, only 2 were flyable (Ta-152C's). The XP-72 first flew in 1944, before the Ta-152 and, if selected for production, could have been in Europe in quantity in 1945. The issue is moot; it is a "what if," and you think differently than I do. No big deal. And you could be as right as I could be, who knows?

We already KNOW how many Ta-152's were flyable at the end of the war. The 2 left were very interesting curiosities, nothing more. They made no difference in the war at all, but were creative aircraft built too late to affect the outcome of the war. The Germans did their best to produce them, but production when being bombed daily is a tough proposition. The U.S.A. was never bombed and could easily have produced the XP-72 in quantity, like we did with other aircraft.

The rate of climb has almost nothing to do with drag. The efficiency of the propeller at climb power and climb speed, coupled with the wing profile and weight to power ratio are the deciding factors. The rates of climb are as published, not by me, but by the people reporting on the aircraft. Surely you don't think we should re-write the published figures, especially with no Ta-152's to fly for confirmation trials? The R-43660 used in the XP-72 made the rated power. Heck, even the R-3350 made 3,500 HP. Today, at Reno, they make 4500+ HP on a regular basis. I have seen one run at 5,000 HP personally.

Your point number 5 shows a lack of knowledge of WWII aero engine operation. NO WWII fighter engines were or are happy with torque changes. They run best at constant RPM, with gradual changes in RPM and manifold pressure. Faster-reacting superchargers mean nothing in service. Suddenly opening the throttle could easily make you a POW when the engine failed. The best action was to cruise at a speed near "best corner speed," which most WWII fighters DID, and it is WAY below maximum speed, even in jets. The best corner speed in an F-16 is near 460 knots. That way, if jumped, they were already at their best corner speed and could quickly react while taking care of the powerplant and gradually increasing power.

The Ta-152 was a pinacle aircraft for the FW-190 series, but don't tell us you have new information that the aircraft was really much better than published. C'mon, it flew as published and as tested.

I have regular contact with Steve Hinton and have asked him on several occasions about the Paul Allen FW-190. It performs to the book; no better, and certainly no worse. It has the BMW-801 radial (restored by Mike Nixon) and makes book numbers when flown to book settings. I have no doubt the Ta-152's exhibit the same German accuracy in flight test as the FW-190 does.

I only represent myself, but the Ta-152's numbers are what they are. So are the numbers for the XP-72, which was not selected for production because everyone already knew the war was winding down in Europe by mid-1944 and the end was only a question of time. Even the Third Reich knew it.

So my opinion is as written above. If someone has facts supporting other numbers, then show them with publically-availble references, not one of those "I have this book and it is the only copy" stuff. None of this "my grandfather knew someone who knew a pilot who said ..." heresay stuff. Good, solid references. I ignore people who publish a scanned text page or pages with no report number, no ID of any kind, and expect everyone to accept it. Any report will have an identification and, if you (or any poster) can get it, then so can anyone else.

Your opinion is, obviously, differrent. That's OK and you could be correct ... but the publically published numbers don't support it.

The Ta-152 wound up with 7 victories against 4 losses. Hardly the "best piston fighter ever." Even the F4F Wildcat was better in combat, if you count the kill-to-loss ratio, and the Ta-152 was flown by Luftwaffe "Experts," mostly.

 

[Dcazz7606]

I found some photos of both XP-72's in Warren Bodies Thund

rbolt.

 

[GregP]

Thanks for the pics! Neat views.

 

[Gixxerman]

That XP 72 is some big brutal looking beasty alright.

 

[DonL]

If someone has facts supporting other numbers, then show them with publically-availble references, not one of those "I have this book and it is the only copy" stuff.

Source: Dietmar Hermann; Focke-Wulf Ta 152: The Story of the Luftwaffe's Late-War, High-Altitude Fighter
http://www.amazon.com/dp/0764308602/?tag=dcglabs-20

In my opinion, the Ta-152's used were service prototypes (the Ta-152H first flew in 1945, later than the XP-72)

The first testlight of a Ta 152 prototype was the flight of FW190 V19, Werksnummer 0041, at 7 July 1943!

The first testflight of a Ta152 H prototype was the flight of FW190 V33/U1, 13 July 1944.

I show the Ta-152H at normal takeoff weight of 5,219 kg

The Ta 152 H-0, which was in combat had a normal takeoff weight of 4730kg.

The Ta-152 wound up with 7 victories against 4 losses. Hardly the "best piston fighter ever."

10 victories against 2 losses. One was shot down, one was lost of unknown reasons and all combat missions were flown totaly outnumbered!

 

[Dcazz7606]

Here's another of the 2nd, counter rotating prop version!

 

[jim]

Mr GregP
I really do not understand your post. The main references i used was Harmann s book on Ta 152, Reschke s book on JG 301/302 history with extensive reports on Ta 152. I imagine i am not the only person i posses these books.I dont have new info on Ta , i am just an amateur On Xp 72 all internet sites i visited report 480-490mph and 3000 hp for the -13 engine. The 540 mph calculations for a militarily equiped piston engine fighter ,regerdless its nationality, sounds to me very ambitious
1) Even if 503mph was correct i insist was impossible for practical use to cruise at 490mph
2) I used normal take off weights for both aircraft . Why we end with diferent results i dont know
3)Ta 152 flown only by experts? I have readen this also elsewhere. Name one pilot of Ta 152 who could be called experte. One. Or experienced formation leader . Actually a Ta was lost when its inexperirnced pilot stalled it on landing procedures . And even if some of them had decent general flying ability , all had very little type experience and no tactics developed.
4)Ta 152 wing was optimized for high altitude but out turned easily late Fw 190A8 and turned with the best alleid low level fighters ( Tempest (3000hp aircraft),Yak9) at low level without Mw50 ,. In fact the specialized low level Tempest stalled and crashed and not the Ta during turning combat.
5) I am not ww2 engine expert, but at least german pilots memories indicate often change of power during combat.And sudden apllications of full throttle. Engine response was important . Jumos 004Bs were badly critisized for their slow response.
6) It is interesting the claim that XP 72 was not produced because everyone knew that war was ending. Then what about F8F, F7F ,P51H, XBT2D-1 , B32 ? No such considerations in their cases?
7)German late war wide blade propellers were optimized for climbing and not speed . My calculations , if correct, show in theory close RoC. Obviusly we use diferent data.
8)The combat history of an aircraft can not bu use the way you do. MIg 29 should be judged by the casualties that suffered in 1991? And there no solid proof that a TA was shot down in combat , and even if did happen was caused by surprise attack
But even if i am totaly wrong why your response was so agressive?

 

[Hoju2k]

One thing that wasn't mentioned in the comparison: the Ta-152 clearly had the best armament of the two.

 

[davparlr]

actually the Ta 152H was superior at mid-alt as it never flew combat ops at the alt. it was required to play ............... this is another misnomer you guys are putting forth from the past documentaion you have all read. superior performance at 40K and beyond was with tests of former JG 301 pilots at least a dozen.

Okay, you seem to have us since you have data we don't. I don't know what you consider mid altitudes, but this is what I have. You will have to tell me where it is wrong. Airspeed data on the Ta is from an Fw chart for EB engine. I am sure you are aware of this chart. Climb for the Ta is questionable.

SL (airspeed-mph, climb-ft.min)
Ta-152 374, 3937+ (without MW50?)
P-51B 386, 4430
P-51H 413, 5120
P47M 365, 4000

15k
Ta 422, 2760+ (without MW50?)
P-51B 428, 3820
P-51H 440. 3650
P-47M 418, 3560

20k
Ta 441, ukn
P-51B 442, 3200
P-51H 463, 3100
P47M 437, 3300

25k
Ta 449, ukn
P-51B 440, 2400
P-51H 466, 2350
P-47M 453, 3000

30k
Ta 467, 2600 (est)
P-51B 430, 1700
P-51H 448, 1700
P-47M 467, 2200

35k
Ta 451, ukn
P-51B 417, 900
P-51H 434, 900
P-47M 475, 900

You will have to let me know if any of my Ta-152H data is wrong. And , if you have climb data, that would be appreciated.

A bold statement impossible to verify. I know little more than what google has to offer about the XP-72, but from that I get no more than two prototypes ever took to the air. The 3 Fw 190 C prototypes with mechanical supercharger likewise showed no vices I know of yet still the Ta 152 had its share of teething issues. Some problems simply only come up over time. In the Ta-152 case the Jumo supercharger gear was the main source of the problems. The XP-72 existed in the form of two prototypes of which one crashed, how many flight hours were accumulated befor the program got cancelled? Did they represent the configuration that was to be produced (e. g. contra-rotating propeller and/or dash 19 engine)?

I agree it is pretty bold. We do not seem to have a lot of data on the XP-72 including test flight hours. However, it is reported that the program was enthusiastically supported, that flight test program went very smooth for a new aircraft, and that the pilots thought highly of it. It is hard to imagine that the aircraft was not thoroughly tested given it was in a production effort. As for the Ta-152, it is reported by Wikipedia that only 31 flt hours had been accomplished by production go-ahead and on 50hrs completed on 20 preproduction units by January, 1945 (some had crashed). I am sure that a lot of problems were uncovered in combat, issues the XP-72 would not have uncovered, but I suspect not many corrections had been made. My statement that the XP-72 was more mature is strictly supposition, but I don't think it is unrealistic.

With all due respect, could we please stop acting like the world is so simple you can just magically pour money and resources into any development or production you want and, by that, speed it up indefinetly?

You do have a point here in that, while production facilities being set up to make the Ta and the Do could be used to set up manufacturing for proven aircraft like the Me-262 and point defense fighters, the limiting factor seems to be resources, most notable fuel and experienced pilots.

Too bad the US spent so much time developing the XP-72, XP-60, XP-67 when they had the P-51 with the P-80 to follow.

The US had the time and money to afford this luxury and Germany did not.

The first testlight of a TA 152 prototype was the flight of FW190 V19, Werksnummer 0041, at 7 July 1943!

I am not buying this. This aircraft appears to be a test bed aircraft that was more akin to the Fw-190D-9 than to the longer, bigger wingspaned, and heavier Ta-152 and certainly not near a production version of the Ta as the XP-72 was.

The first testflight of a TA152 H prototype was the flight of FW190 V33/U1, 13 July 1944.

This I'll buy, however there is a footnote in that it crashed the next day and there was a months delay until the next prototype flew.

THe main differences was the other wing design and pressurization cockpit.

.
Neither minor changes.

Do you have any source or book about the TA 152, that would back up your claim?

Wikipedia references lack of time to iron out the various problems associated with new aircraft and both Wikipedia and Wagners "German Combat Planes" references the prototype crashes.

The TA 152H hat a climb rate of 20m/s at Sea Level and a climb time of 8 min to 7000m without MW 50 better then a P51D from the B I don't want to talk!

Wow, you make this sound impressive. However, the P-51B, as shown in the referenced test, at Mil power (67" Hg), which should be equivalent to non-MW-50 Ta, has a climb rate of about 3750 ft/min (19 m/sec) at SL slightly less than the Ta-152H. However, in time to climb, note that the P-51B will reach 7km (22,965 ft) in about 7 minutes, much better than the Ta. Significantly, the P-51B with Normal power (61" Hg) reaches 7 km in about 7.5 minutes, still better than the Ta! This test was run at two hundred pounds over the fighter weight of the P-51B, 9335 lbs. The fighter weight of the P-51B is about 9160 lbs. 100 ft/min ROC would have to be added to the SL ROC to get the P-51B Mil number. Time to climb for the B would be slightly faster than noted above. About a 100 ft/min has to be subtracted for the P-51D SL ROC. Time to climb would be slightly longer than noted above.

Now, looking at airspeed comparing the Ta with MW-50 with the P-51B at 75" Hg. (approved May, 1944 by AAF) also tells an interesting story. The P-51B (without racks) is faster up to 20k and only slightly slower at 25k.

So, in summary, the June, 1944, P-51B/D was going to out climb the 1945 German best Ta-152 to 23k, and be competitive in airspeed all the way up. Only at 25k and above was the Ta clearly superior to the P-51B/D whether you don't want to talk, or not!

Above 25k? Well there was the P-51H and P-47M. And P-72? A little note here, at 30k, the P-47M was producing over twice the hp of the Ta-152.

This is all true if the data on the Ta-152H is accurate!

http://www.wwiiaircraftperformance.org/mustang/P-51B_24777_Climb.jpg

Test pilot Tom Bellinger stated flatly that the no flights ever exceeded 500 mph. The dash 13 engine was not supercharged. With the planned but never installed dash 19 engine (with a remote supercharger) rated at 3,650 HP at 25,000 ft. (3,000 HP at sea level) a top speed of 504 mph at approximately 25,000 feet was expected. Planned further development of the dash 19 engine was expected to yield approx 4,000 hp and a speed of 540 mph at 25,000 ft.

I am confused as to the exact supercharger configuration of the XP-72. I suspect that the shaft driven supercharger was installed on the XP-72. I find it hard to believe a non supercharged engine could power a plane to 480 mph at 25k ft without one, even if it is producing 3000 hp at SL. I think a proposed turbo-supercharger was not installed. I think the dash 19 engine was only the production version of the -13.

Hence we are comparing a XP-72, which achieved 480mph in level flight during its test program with a Ta 152 which achieved 472 mph also in test but also achieved production and service. The key difference is service ceiling with the Ta 152 likely higher due to its high aspect ratio wings.

A turbo-supercharger could easily move this number towards 500 mph, but I would never bet on much above that from any prop plane from WWII.

 

[davparlr]

Mr GregP
I really do not understand your post. The main references i used was Harmann s book on Ta 152, Reschke s book on JG 301/302 history with extensive reports on Ta 152. I imagine i am not the only person i posses these books.I dont have new info on Ta , i am just an amateur On Xp 72 all internet sites i visited report 480-490mph and 3000 hp for the -13 engine. The 540 mph calculations for a militarily equiped piston engine fighter ,regerdless its nationality, sounds to me very ambitious

I agree

1) Even if 503mph was correct i insist was impossible for practical use to cruise at 490mph

300 mph is the cruise speed for the XP-72

5) I am not ww2 engine expert, but at least german pilots memories indicate often change of power during combat.And sudden apllications of full throttle. Engine response was important . Jumos 004Bs were badly critisized for their slow response.

Early turbojets were notorious on throttle sensitivity. However, this did not apply to turbochargers. I am not sure but I suspect turbocharger rpm remain high whether it was loaded or not. Others know more.

6) It is interesting the claim that XP 72 was not produced because everyone knew that war was ending. Then what about F8F, F7F ,P51H, XBT2D-1 , B32 ? No such considerations in their cases?

F8F, F7F, and XBT2D-1 were Navy planes and jet operations off carriers was uncertain. P-51H was much cheaper and further along. B-32 was already developed but problematic. It fell victim just like the XP-72 only it was further developed before the end of the war was known.

8)The combat history of an aircraft can not bu use the way you do. MIg 29 should be judged by the casualties that suffered in 1991? And there no solid proof that a TA was shot down in combat , and even if did happen was caused by surprise attack

How many of the Ta-152 kills were surprise attacks?

 

[pinsog]

One thing that wasn't mentioned in the comparison: the Ta-152 clearly had the best armament of the two.

They were supposedly entertaining 4 37mm cannon as alternative armament for the P-72. What exactly they planned to shoot at with that kind of armament, I don't know.

 

[Hoju2k]

They were supposedly entertaining 4 37mm cannon as alternative armament for the P-72. What exactly they planned to shoot at with that kind of armament, I don't know.

Yeah well, you can't expect the same perfomance with that armament. Also, for the Ta 152C, different combinations were planned, such as 4xMG151 + 1Mk103, or 3x Mk103, all with the great advantage of being mounted in the fuselage and then don't have to deal with the convergence issues. But I think we should stick with what they actually had.

 

[wuzak]

I am confused as to the exact supercharger configuration of the XP-72. I suspect that the shaft driven supercharger was installed on the XP-72. I find it hard to believe a non supercharged engine could power a plane to 480 mph at 25k ft without one, even if it is producing 3000 hp at SL. I think a proposed turbo-supercharger was not installed. I think the dash 19 engine was only the production version of the -13.

A turbo-supercharger could easily move this number towards 500 mph, but I would never bet on much above that from any prop plane from WWII.

I don't believe that the XP-72 was ever intended to carry a turbocharger.

The compressor driven by the extension shaft was the first stage of a two stage system - the engine retaining its integral supercharger.

If the XP-72 ran without the first stage supercharger then it is possible that the engine supercharger was rated for the XP-72's maximum speed altitude.

The XP-72 was heavily based on the P-47 with its rear fuselage mounted CH-series turbocharger. The reasoning behind the auxiliary (or first stage) supercharger being mounted in the rear fuselage and driven by an extension shaft was to maintain weight balance. I suspect, therefore, taht the auxliary supercharger was fitted, even if it wasn't operational.

 

[wuzak]

Heck, even the R-3350 made 3,500 HP. Today, at Reno, they make 4500+ HP on a regular basis. I have seen one run at 5,000 HP personally.

The R-3350 only made 3500hp with turbo-compounding. The best a non-turbo-compound production engine managed was about 2800hp - but a few years after WW2. As far as I know the R-3350 was only ever rated for 2200hp during the war.

At the end of the war both the V-1710 and Merlin were being, or about to be, rated at 2200hp. The V-1710-127 (the turbocompound prototype) was rated at 2900hp - but the turbine used couldn't cope with the exhaust temperature.

As for one offs the Merlin RM.17SM managed 2600hp in 1944 - for a 15 minute run. For Reno Merlins are tuned to over 3500hp. But how long can a Reno Merlin run at that power, or a Reno R-3350 run at 4500hp?

 

[Shortround6]

It is not just a question of how long they could run but how long running at such levels shortened the scheduled time to overhaul. American engines WEP power level had to achieved by a test engine running 7 1/2 hours at those levels although it could be done 5 minutes at a time. There are stories of Lockheed test pilots at the end of the war (or in the week or two after) taking off at WEP and dog fighting (chasing each other) without ever backing off the throttle until low on fuel and having to land. The acceptance flights had to flown for contract reasons but the planes were going straight to a maintenance/scrap yard.

Some aircraft engines show a rather amazing (and alarming) ability to withstand some extreme abuse in one flight only to fail catastrophically 1 to 2 hours into the next flight when being flown normally. I rather doubt that Reno race engines, after being flown in one race are expected to provide another 300-400 service before their next overhaul/tear down.

There may be a reason that by the end of the war a Merlin for transport service was rated as having a life 150-200 hours longer than a fighter Merlin.

 

[GregP]

You know guys, I can add several comments.

1) My databse is the result of about 15 years of research by me. The source I used about 10 years ago gave only two weights for the Ta-152H-1, and one was the weight I quoted. After reading the replies above I went to several other sources and found three weights, empty, normal takeoff and max takeoff. So, I stand corrected there, and also corrected my database. Unless I have a reason to suspect inaccuracy, I usually don't revisit my database entries. In this case, the entries were not inaccurate; the middle weight was missing.

2) All my sources list the max speed as 472 mph @ 41,010 feet for the Ta-152H-1.

3) All my sources list the initial climb rate as 3,445 feet per minute for the Ta-152H-1.

4) I have 5 sources that say 503 mph for the XP-72, one source that says 480 mph, and two source that say 490 mph. We have also had a former Republic test pilot give a talk at the Planes of Fame Museum and he stated the XP-72 was a real wonder and DID have a climb rate of more than 5,000 feet per minute and a top speed slightly over 500 mph. As for cruise speed, I can find no mention of it aside from a reported 490 mph in one source and a reported 300 mph at teh National Museum of the Air Force. I confess I am skeptical about a 490 mph cruise too, but I cannot find any reliable reference to cruise speed. It was, after all, only a prototype.

If you believe the National Museum of the Air Force for the 300 mph cruise, then you also believe the 3500 HP engine rating. You can't choose one number and say it is OK, but another number isn't. Your choice yes or no.

I only found one single reference with a reason listed for not producing the XP-72, and it stated that there was a greater need for long-range excorts in Europe than for the XP-72. The person who said it was not produced because the war was winding down was the former Republic test pilot mentioned above. We have had talks by a LOT of former test pilots, most American, some German, some British, one Japanese, and one Dutch.

I have 6 sources for the Ta-152. Four of them mention the operational results. Three say 7 victories and 4 losses. One says 7 to 10 victories, depending on who you believe, and 4 losses. Persoanlly I don't think it makes any difference if the victores are 7 or 10 ... or even if the real losses are 2 or 4. Either way, the combat record is not impressive, at least to me. You may well think differently, and that is just fine.

As to Davepark's question about the other aircraft being produced, I was not there and do not know. I have been told one reason by a former test pilot of the XP-72 and have no contact with anyone else who has knowledge of why some aircraft were produced and some weren't. To me, it is VERY likely that politics had more to do with the decision than aircraft performance, just like it did when Canada cancelled the CF-105 Arrow and the famous British White Paper and the General Dynamics F-111. In each case, politics decided, not the evaluation report of the aircraft performance. Test pilots had and have no say in production awards. These are the exclusive property of the US Senate and House of Representatives. If the congress votes to produce an aircraft, it gets built. If they don't so choose, it doesn't.

I like the XP-72 and choose to believe it was a better aircraft than the Ta-152. I could be right or wrong. History won't say becasue the XP-72 was not selected for production. So, I am left with my own opinion and reasoning. Since I usually detest "what ifs," I usually don't get involved with them. This time I stumbled over that and chimed in on the side of the XP-72. Since it is a big "what if," I'll back out of the thread going forward and state that the XP-72 would have been an interesting addition to the combatants in WWII ... but wasn't since it wasn't produced. Both Ta-152's operating at the end of the war were interesting, too, but that is about all they collectively achieved.

Germany claimed 43,765 enemy aircraft shot down in WWII. The contribution of either 7 or 10 is insignificant in the extreme. But I still like the Ta-152 a lot, just based on looks and innovation.

The XP-72 made zero difference in WWII because it never saw action. But I still like the aircraft based on projected performance potential.

 

[Shortround6]

3) All my sources list the initial climb rate as 3,445 feet per minute for the Ta-152H-1.

4) I have 5 sources that say 503 mph for the XP-72, one source that says 480 mph, and two source that say 490 mph. We have also had a former Republic test pilot give a talk at the Planes of Fame Museum and he stated the XP-72 was a real wonder and DID have a climb rate of more than 5,000 feet per minute and a top speed slightly over 500 mph. As for cruise speed, I can find no mention of it aside from a reported 490 mph in one source and a reported 300 mph at teh National Museum of the Air Force. I confess I am skeptical about a 490 mph cruise too, but I cannot find any reliable reference to cruise speed. It was, after all, only a prototype.

If you believe the National Museum of the Air Force for the 300 mph cruise, then you also believe the 3500 HP engine rating. You can't choose one number and say it is OK, but another number isn't. Your choice yes or no.

3. A big problem I am finding when researching the climb rates of various planes is that very often no power rating is given for a particular climb rate. It also seems that different countries used different standards which wind up being rather confusing. I don't know how the Germans reached this figure. But as an example of differences I would note that the British "usually" measured climb rate using a 30 minute "climb rating " for the engine. The Americans would often use "military power" for the first 5 minutes and then use "max continuous" (which for american engines was a 1 hour or until the fuel ran out, so it is a lower rating than the British would use) for the rest of the climb and the higher altitude climb figures. Obviously the use of WEP ratings would change things considerably. Getting back to the Ta-152 , is that climb rate using a 30 min climb rating (a power level used by the Germans?) or a "full throttle climb" or climb using MW-50? (if the plane was so equipped).
Sometimes you can find tests that were done at WEP or emergency power but if you are comparing one plane's numbers using WEP to another that is not using using WEP (assuming it had such a rating) things are going to be somewhat off even though BOTH numbers are true.

4). Cruise speeds are even worse. Cruise speed at Maximum continuous power? At maximum lean power? Most economical? greatest endurance? and at what altitude? A P-47B could be cruised at 12,000ft using 65gph for economy or at 160gph at max continuous power ( at which setting it was doing 300mph at 12,000ft.) At 25,000ft the P-47B could "cruise" at 360mph true using 190gph.
I can certainly believe the P-72 could cruise at 390mph ( a simple typo from 490mph?) and even a P-47B could cruise at 25,000ft at 300mph using just 95gph.

Engine ratings for the R-4360 as used in the XP-72 are a bit iffy. Sources do differ but with few engines of that model made getting good information is hard. most sources say 3000hp but that is military power. these sources will also give 2000hp or 2100hp for P-47 engines depending on model and not give the WEP power ratings. Did the R-4360 AS USED in the P-72 get a WEP rating? if so was it 3500hp or was it expected to get 3500hp? I would note that the plane with the 4 bladed prop and the plane with the counter rotating prop used different dash number engines even if not noted in accounts of the plane.