Ta152H1 high altitude speed

[TempestMKV]

Focke-Wulf Ta 152-H1 Specifications:
Crew: One
Powerplant: Junkers Jumo 213E-1 12-cylinder, liquid-cooled engine rated at 1,750hp at take-off ( 2,050hp with MW 50 ) and 1,320hp at 32,800ft. (1,740hp with GM 1)Armament: 1 x 30mm Mk108 cannon mounted in the engine with 90 rounds, 2 x 20mm MG151/20 cannon mounted in the wign roots with 175 rpg.
Gunsight: Revi 16b reflector sight
Max. Speed: 332 mph @ sea level (350 mph with MW 50), 465 mph @ 29,530 feet (with MW 50), 472mph @ 41,010 feet (with GM 1)
Cruising Speed: 311 mph cruising speed at 22,965ft.
Range: 755 miles to 1,250 miles depending on speed and external tankage
Fuel Capacity - internal 260.6 gallons external: 158.5 gallons
Climb - initial 3445 fpm with MW 50 injection Time to Altitude: ?
Ceiling: 48,550ft. with GM 1 injection
Dimensions - wingspan: 47 feet 4.5 inches length: 35 feet 1.66 inches height: 11 feet 0.25 inches wing area: 250.8 square feet
Weights: 8,642 lbs empty, 10,472 lbs operational, 11,502 lbs max.
Operational Wingloading: 41.75 lbs/square foot
Number deployed: exact figure unknown but 20 pre-production H0's and 34 production H1's seem to be a generous estimate.

At 10000 meters, ie 33000feet, Ta152H1(with GM1) engine output should be around 1740 HP, max speed should be about 470-475m/h.

On the other hand, P47M R2800-57 output @ 10000m/33000feet is nearly 2800HP while maxspeed is 473m/h.

Anyone can explain how could Ta152 achieve same max speed with 1000HP smaller than P47M? Martian technology?

REPUBLIC AVIATION
Corporation Report No. ES-300
Farmingdale, L. I., New York Model AP-16a

October 14, 1944
Model Specification for
Republic Model ?AP-16a
Fighter Offensive
Air Corps Type Designation P-47M

Performance (With Design Useful Load)
(1). Guaranteed Performance
(a) High Speed at 38,750 ft. (Critical Altitude) with 2100 BHP 462 MPH
(b) High Speed at 15,000 ft. with 2100 BHP 383 MPH
(c) High Speed at 5,000 ft. with 2100 BHP 350 MPH
(d) High Speed at 42,000 ft. (Critical Altitude) with 1700 BHP 441 MPH
(e) Operating Speed at 32,000 ft. (Design Alt.)
with 1270 BHP (75% Normal Rated Power 91% Rated RPM) 360 MPH
(f) Endurance at Operating Speed with normal fuel load (205 gals.) 1.48 hrs.
(g) Time to Climb to 15,000 ft. 5.7 min.
(h) Take-Off over a 50 ft. obstacle within 2,200 ft.
(i) Landing over a 50 ft. obstacle, within 2,150 ft.
(j) Landing Speed with Flaps retracted 118 MPH
(k) Landing Speed with Flaps extended 99 MPH
(l) Cruising Speed at 20,000 ft., 820 BHP at 1800 RPM 246 MPH
(m) Range at Cruising Speed with 205 gals. of fuel 785 miles

(2). Additional Performance
(a) High Speed at 32,000 ft. (Critical Altitude) with 2800 BHP (W.E.P.) 473 MPH
(b) High Speed at 15,000 ft. with 2800 BHP 418 MPH
(c) High Speed at 5,000 ft. with 2800 BHP 384 MPH
(d) Time to Climb to 15,000 ft. with 2800 BHP 4.2 min.
(e) Take-Off over a 50 ft. obstacle, at 2800 BHP within 1,800 ft

Furthermore, at 30000 feet/ 9000m:

P47M max. speed 469km/h 2800HP
Ta152 max. speed 465km/h 1400HP- with MW50, without GM1

2800HP vs 1400HP, same speed. Why?

 

[TempestMKV]

As water-cooled engine, 21lbs spitfire XIV output is 2050HP @SL just same as Ta152 @SL. 21lsb Spitfire XIV is slightly faster than Ta152 @SL.

At 9000m, both Ta152 with MW50 and spitfire XIV outputs are 1400HP or so. However, Spitfire XIV max speed is 443m/h while Ta152 is 465m/h!


Great Martian technology of Ta152!

 

[HoHun]

Hi Tempest,

>Anyone can explain how could Ta152 achieve same max speed with 1000HP smaller than P47M? Martian technology?

Exhaust thrust.

Regards,

Henning (HoHun)

 

[kool kitty89]

Not to mention they were completely different aircraft with different drag characteristics, the Ta 152 being roughly 4,000 lbs lighter and with a much grater frontal area.

If you look at the P-47 alone, compare the P-47M to the XP-47J. The XP-47J was a bit lighter, but not hugely, it used the same engine and airframe, and similar propeller but managed 507 mph in testing at 34,300 ft. The key difference? The XP-47J utilized a tight fitting, streamlined engine cowling with a large, conical spinner with a cooling fan. This dramaticly reduced the aircraft's parasitic drag. (similar cowlings were used by the Fw 190A, pretty much all BMW 801 installations, the Hawker Tempest II and Sea Fury, the J2M Raiden, several prototypes in the US, and I beleive the Soviet La-5/7)

 

[delcyros]

Hi TempestMKV,

You encountered a systematic error in Your data´s for the P-47M. Your data´s show no engine output difference at allfrom 0 to 5000 to 32000ft for the R-2800-57. This is likely the cause for the difference. I may be wrong but can´t imagine any piston engine to have no change in poweroutput at altitude this way or another.
Just as a pointer to check that aspect, hope this helps,
Delc

 

[Kurfürst]

Hi Tempest,

>Anyone can explain how could Ta152 achieve same max speed with 1000HP smaller than P47M? Martian technology?

Exhaust thrust.

Regards,

Henning (HoHun)

I guess long span wings, and having an inline engine in an airframe strongly resambling a fighter instead of a locomotive with an enormous radial also helps. 8)

 

[Kurfürst]

Hi TempestMKV,

You encountered a systematic error in Your data´s for the P-47M. Your data´s show no engine output difference at allfrom 0 to 5000 to 32000ft for the R-2800-57. This is likely the cause for the difference. I may be wrong but can´t imagine any piston engine to have no change in poweroutput at altitude this way or another.
Just as a pointer to check that aspect, hope this helps,
Delc

Its normal, the curve is like this because the P-47's turbocharger - it doesn't take any power to run from the engine itself, so no increasing supercharger power requirements with altitude. The downside is as HoHun noted, lack of thrust gained from exhaust, and the bulk of the turbo system.

 

[runningdog]

Aeroplanes is aeroplanes, they don't always do what you expect them too, a bit like folk I suppose...........

 

[Njaco]

I guess long span wings, and having an inline engine in an airframe strongly resambling a fighter instead of a locomotive with an enormous radial also helps. 8)

Thats it right there!!!

 

[TempestMKV]

Not to mention they were completely different aircraft with different drag characteristics, the Ta 152 being roughly 4,000 lbs lighter and with a much grater frontal area.

If you look at the P-47 alone, compare the P-47M to the XP-47J. The XP-47J was a bit lighter, but not hugely, it used the same engine and airframe, and similar propeller but managed 507 mph in testing at 34,300 ft. The key difference? The XP-47J utilized a tight fitting, streamlined engine cowling with a large, conical spinner with a cooling fan. This dramaticly reduced the aircraft's parasitic drag. (similar cowlings were used by the Fw 190A, pretty much all BMW 801 installations, the Hawker Tempest II and Sea Fury, the J2M Raiden, several prototypes in the US, and I beleive the Soviet La-5/7)

That makes sense.
BTW, anyone can provide Griffon65's output above 9000m?

 

[kool kitty89]

Another good example is comparing planes like the P-51 and P-38, P-51H to P-47M, or He 162 to the Me 262, the Me 262 has roughly double the thrust but is also much larger, while the performance is fairly similar. (the He 162 actually faster with the emergency overrev of the BMW 003E)

The P-51H's case is particularly good as it's fairly comparable in size to the Ta 152 (though closer to the 190), but a bit lighter and with smaller wings and no cockpit pressurization. (the Fw 190D-11/13 with the same engine as the Ta 152 -minus the GM-1 would be very comperable to the P-51H and still much different than the P-47)

Again, they're just different aircraft with different characteristics.

 

[TempestMKV]

Another good example is comparing planes like the P-51 and P-38, P-51H to P-47M, or He 162 to the Me 262, the Me 262 has roughly double the thrust but is also much larger, while the performance is fairly similar. (the He 162 actually faster with the emergency overrev of the BMW 003E)

The P-51H's case is particularly good as it's fairly comparable in size to the Ta 152 (though closer to the 190), but a bit lighter and with smaller wings and no cockpit pressurization. (the Fw 190D-11/13 with the same engine as the Ta 152 -minus the GM-1 would be very comperable to the P-51H and still much different than the P-47)

Again, they're just different aircraft with different characteristics.

.....I am intersted in "Spitfire XIV HF with critical height=30000feet, plus liquid oxygen" which is possible in history.

 

[TempestMKV]

This is the output chart of Ta152H1(Jumo213E) and 21lbs spitfire XIV(Griffon65).

The pink line is of SpitfireXIV; and red line is supplementary of output with Gm1. There are 3 flow rates of Gm1, so 3 lines; the blue line indicates the Ta152 output if the 3rd speed is broken which sometimes occurs. LOL


As we can see, at sea level, spit and Ta152 share same engine output and same max. speed, however, at 30000 feet, Ta152H is 35km/h faster than spitfireXIV while spitfire's output is greater. So the Ta152's max speed of 465m/h@30000feet is quite suspicious. I prefer that's the result of Gm1 or under no weapon condition.

BTW, it's no use of turning on MW50 above 7k altitude.The max. speed with MW50 at 9000m is just ridiculous.

Jumo213E's 2-stage 3-speed supercharger shares same performance with Griffon's 2-stage 2-speed......

If Britain brought out Spitfire XIV HF or liquid oxygen, the GM1 would be overcome above 10k meters, what a bad news for Ta152!

Above10k, 17min GM1 operating is Ta152H1's only hope; below 10k, both Ta152 and Dora are outperformanced by 21lbs boost Spitfire XIV.

 

[HoHun]

Hi Tempest,

>As we can see, at sea level, spit and Ta152 share same engine output and same max. speed, however, at 30000 feet, Ta152H is 35km/h faster than spitfireXIV while spitfire's output is greater. So the Ta152's max speed of 465m/h@30000feet is quite suspicious.

Exhaust thrust.

As long as you don't understand that, all your assertions are just nonsense.

Regards,

Henning (HoHun)

 

[TempestMKV]

Hi Tempest,

>As we can see, at sea level, spit and Ta152 share same engine output and same max. speed, however, at 30000 feet, Ta152H is 35km/h faster than spitfireXIV while spitfire's output is greater. So the Ta152's max speed of 465m/h@30000feet is quite suspicious.

Exhaust thrust.

As long as you don't understand that, all your assertions are just nonsense.

Regards,

Henning (HoHun)

Then tell me why Exhaust thrust can't help Ta152H1 at seal level?

Does Spitfire XIV have no Exhaust thrust?

R.A.E. Ref: 1465R/WS/140

1. Summary

Performance measurements of top level speeds at low altitudes have been made on Tempest V, Mustang III and Spitfire XIV aircraft, as received from Squadrons operating against the German flying bombs.

Improvements on the top level speed of the Tempest V were 5 ?m.p.h. due to improved quality of finish and 20 m.p.h. due to increasing the boost pressure from +9 to +11 lb./sq.in.

On the Mustang III the wings were cleaned up and the bomb racks and a small bracket at the base of the whip aerial removed giving a total increase of 21 m.p.h. It is estimated that the separate effects were 12 m.p.h. for improved finish and 8 and 1 m.p.h. for the bomb racks and aerial bracket respectively. Replacing the exhausts by Spitfire type stubs gave a further increase of 1 ?m.p.h.
Improved quality of finish on the Spitfire XIV gave 8 m.p.h. increase in level speed. The boost pressure was increased from +19 to +25 lb./sq.in. but only two level speed measurements were obtained. These indicated an increase of 28 m.p.h.

....

At low altitudes and at 25 lb./sq. in. boost, the original exhausts are inadequate in providing the optimal exit area. The exhausts were therefore replaced by Spitfire type stubs representing approximately the correct area required. These were the only type available at the time. No exhaust shrouds were fitted in either case.

Furthermore, I'll amend my opinion, Let's see this chart.

The A, B, C points stand for the three FTH (full throttle height) where pilot push 100% throtle and just get max boost pressure.

The red lines indicate the Jumo213E engine is on Max. boost, so between 8k-10k meters, Jumo213E in on Max. boost with MW50, and below 11k meters, pilots dare not turn on GM1,otherwise, the boost exceeds enigine's ability ...

Conclusion: at 32500feet/9848m ,no GM1 turning on, Jumo213E can NOT acheive 1740HP.

 

[delcyros]

Kurfürst, thanks for the hint. I stand corrected about the crit altitude performance. Just still think that it´s worth to see an actual poweroutput graph for the R-2800-57 with boost levels involved.

"There are reports that XP-47J actually attained 507 mph at an altitude of 34,300 feet. 2,800 hp is 133% of rated power. At military power (100%), the XP-47J could sustain 470 mph. 435 mph was attained at 81% of its rated power (1,700 hp). All performance figures were obtained at 34,300 feet."

That sounds comparable to me: 2100 hp @ 34.3000ft giving 470 mp/h on the XP-47J while
2.100 hp(GM-1, at Kampf- u. Steigleistung) @ 38.000ft, giving 462 mp/h on the Ta-152H

It´s possibly not perfectly comparable as the considitions are unknown but it appears to be indicative for beeing in general congruence. You should ask the question what happened to the P-47M that it´s performance was reduced so appreciably?

 

[Kurfürst]

This is the output chart of Ta152H1(Jumo213E) and 21lbs spitfire XIV(Griffon65).

The pink line is of SpitfireXIV; and red line is supplementary of output with Gm1. There are 3 flow rates of Gm1, so 3 lines; the blue line indicates the Ta152 output if the 3rd speed is broken which sometimes occurs. LOL

....

Jumo213E's 2-stage 3-speed supercharger shares same performance with Griffon's 2-stage 2-speed......

I don't really think so, you seem to be comparing the Griffon 65's output with 400 mph of ram - which will push the curve to the right, ie. like having a higher rated altitude - while the the Jumo 213E power curve is static (0 mph).

Apples and oranges...

 

[HoHun]

Hi Tempest,

>Then tell me why Exhaust thrust can't help Ta152H1 at seal level?

I'm not going to ram down knowledge down the throat of a struggling loudmouth who already has his mind made up. My time is too precious for that.

If you seriously want to learn, ponder the question what is different between an engine at its full throttle height and an engine way above its full throttle height, even if the two have the same shaft power at that height ...

Regards,

Henning (HoHun)

 

[DerAdlerIstGelandet]

Keep the thread civil people...

 

[mad_max]

Anyone here think about the density of air at 30-35-40k affecting drag characteristics?

Engine volume and the engines efficiency at various alts. will also play a roll.

As for exhaust thrust the Jumo will have more than the turbo Pratt, but the Jug still has exhaust thrust.

Also at those high speeds the instruments of the days were questionable. Even
the position of the pitot tube could add or subtract speed. Just look at the Navy study
between the F4U and the Hellcat. Ended up both had basically the same speeds.