Why people think the 51D is so uber?

[Karnak]

F4UDOA,

Keep in mind that both us and the Brits modified a Spitfire to have Mustang class range in 1943?.  If the Mustang had not, for whatever reason, panned out it is likely that long range Spit's would have been pressed into service.

Unsurprisingly adding all that fuel to the Spitfire did bad things to its performance and handling.  In particular I was amused that the fuel tank added behind the pilot made it dangerously unstable and combat would have been forbidden until it was burned off, just as in the P-51.

[F4UDOA]

Kev/Karnak,

As Karnak mentioned the Spit was fitted for long range (I am not sure of the details) however not all aircraft want to do the long range high speed cruise. What I mean by that is that the P-51D could cruise at low fuel consumption at roughly 60 gallons per hour and fly 1900Miles at 300 miles per hour with internal fuel and two 75 gallon dt's.

As Karnak mentioned the weight increase in both is substantial enough to muck up the handling nicely on both. However the P-51D with enough fuel on board to fly over 1,000 on internal fuel at a weight of 9700LBS could still do this.



Not bad for a Heavy fighter.

The Spit XIV could beat that but not with the same fuel load or nearly the same range. The performance gap narrows quite a bit the more things you hang onto the Spitfire to get it to do what the Pony could do with a standard load although not as spectacularly.

I don't know who said it but it is a true statement "The Mustang won't do what the Spitfire will do but it will do it over Germany".

The Mustang was not an Uber dogfighter but it was an Uber Escort.

BTW, have you ever read about the guy who tried to get his Griffon Spitfire to the Air Races? He had a  very interesting opinion on the Spitfire at highspeed flight.

[HoHun]

Hi F4UDOA,

>What does it mean corrected for compressability?

Compressiblity is best know for screwing up your flight dynamics, but it also increases dynamic air pressure. Since the airspeed indicator operates on dynamic air pressure, it will misread noticably at high Mach fractions.

>What should I be looking for?

In the British tests, there is a separate column "compressiblity error" in the test data listing. In German tests, it's documented by indices, so compressiblity corrected true air speed might be listed as "Vwck". If there is a position error table or graph, it might be noted below.

>The combat range can be seen the Aircraft comparison chart from Vought that used the Navy's F-1 combat formula to determine effective range. The range on internal fuel was approx 1,000 miles one way. I can scan and post if you want it.

Thanks, that would be highly interesting! :-)

The comparison table is quite good stuff, too. We have one fairly complete range comparison based on identical mission profiles now! It's a Navy mission profile, and I'm sure USAAF mission profiles were a bit different (flown at greater altitudes), so they probably gave better total range. I don't think the relative ranges should change too much, though.

The problem I spontaneously see with the table is that the number and size of the drop tanks used is not mentioned, so it's difficult to say whether all aircraft are loaded up to the maximum. The P-51B has a shorter range than the P-47D in the Navy listing, which is surprising considering that the P-51B's selling advantage over the P-47 was longer range. Maybe the P-47D was a later model with larger drop tanks, and the P-51B an early one with smaller ones? Hm ...

Regards,

Henning (HoHun)

[Kev367th]

Hi F4UDOA,

No doubting both the Spit and Pony were extremely well suited for their missions, but neither were particulary 'uber'.

Only 'uber' fighter of WW2 was the 262, and perhaps the Meteor III. (No one side had a big performance advantage prior to these)

By the time the Griffon Spits came out Supermarine had all but pushed them to their limits.
This resulted in a redesigned wing for the F.21, and a laminar flow wing for the Spiteful.

F.21 was cancelled after the end of the war (100+ being built and delivered ).
Spiteful cancelled once it was realised the laminar flow wing held no great advantages with the onset of the jet age.

[Karnak]

F4UDOA,

The Spitfire would not have been as good an escort fighter as the P-51 was.  It could have been pressed into service as one, but it would not have done the job as well.  The cruising speed would be substantially lower.  I don't know if a Griffon Spit could have done it though.


As to the air races, I seem to recall a comment about the radiators acting like air brakes when they opened as the coolant tempature climbed.  It did well until the radiators opened.  The Spit's radiator design is simple and crappy compared to the P-51's.

[F4UDOA]

Kev,

>Only 'uber' fighter of WW2 was the 262, and perhaps the Meteor III. (No one side had a big performance advantage prior to these)

Agreed!! IMHO the peak of fighter design occurred in the 1950's. They may be better but they will never be as cool. I love my F4U's but I also love the B-58 Hustler, F9F Panther/Couger, F-86, Vampire etc. Again not uber just cool as can be.

HoHun,

Thanks for the explanation. I have seen it many times but never understood what it represented. I did not see it mentioned in the NAVAER documents but I will definitley revisit my files and search for some examples. Does it make a difference what the critical mach number is on the aircraft or is it dependand on speed and altitude only? Just wondering if I am more likely to see it on different A/C.

I think the Vought document shows the P-51B with 180 gallons of internal fuel. Had it been the D with 260 gallons I am sure it would shown better. I am not familiar with a similar AAF protocol.

Karnak,

That is the artical. I have seen interviews with the pilots of the OFMC where they speak of the P-51 as being a strickly high speed airplane and the Spitfire as being somewhat relucant at higher speeds but being very fluid at low to medium speeds. Annecdotal but interesting never the less.

[Kev367th]

Interestingly  -
A specially modded Spit IX with fuselage tanks and able to carry Pony drop tanks flew from the UK to USA via Iceland for trials.

Must have been a somewhat sphincter twitching flight, single engine over the North Atlantic.

EEEEKKKKKK

[Angus]

Those were 2 Spitfires actually

[gripen]

F4UDOA,
IMHO the best way to understand the relation between compressibility and IAS/CAS is to understand that the airspeed indicator reading is calibrated for certain conditions (say CINA standard atmosphere at sea level or what ever). So the CAS reading given by the meter (ie reading with position error) at these conditions contains very little error but when the conditions (altitude, temperature etc.) change these should be corrected. In other words IAS/CAS reading normally contain some compressibility correction but it's correct just for given conditions.

There are couple ways to check if the claimed speed contains compressibility error if it's not claimed. Simple way is to convert known IAS to TAS with standard conversion chart, if the difference between claimed and converted speed increase when the altitude increase (below FTH) claimed being faster, then it's very likely that the claimed speed is without compressibility correction.

The more complex way is to calculate drag from claimed speed with known power curve and quessed (or known) prop efficiency; if the drag decrease when the altitude increase, the claimed speed is probably without compressibility error.

But because the conditions tend to vary, these are just good quesses. Good data sets contain documentation on conditions and corrections; less room for uncertainty.

gripen

[Nosara]

one .30 from a 109 and poof...no pony.

[Ack-Ack]

Originally posted by DiabloTX
Soccer war.

From the Wiki: "The war is often cited as the last occasion on which piston engined fighters fought each other - both sides deploying former World War II American types. P-51 Mustangs, F4U Corsairs, T-28 Trojans and even Douglas DC-3s converted into bombers saw action. The Salvadoran Air Force was so out of shape that they reverted to dropping bombs by hand from the windows of their planes."

P-38L saw some of that action too...think it was with the Honduran AF.


ack-ack

[Nemeth]

Originally posted by DiabloTX
Im gotta go wit teh Sptfire cuz its all kewl n stuff wit teh canins go pow! pow! pOw! n teh wings sooo kewl n i no that it culd blaze a 109 all ur base r belong to meh!!11!1111!!

WOW what a poser! (and its all your base are belong to us)
i dont kno why ppl think the p51 was so good, a full fuselage tank made the plave VERY unstable in fights, with the amount of gas its held, it would blow up from only a few bullets, yes the speed is good.

But when ppl say the mustang won the war, they are wrong... its not the plane that won the war, its the people who flew the planes, the people that built the wepons, the vehicles, the botas and the planes, AND MOST OF ALL, the people that fought the war, both the people that survived and died.

If u want to argue me about this go ahead, HTC will prob lock this if 2 many peole do.

[Kurt]

Sas, You can't apply AHII to your history classes.  It is a game.

The P51 was one of the most capable fighters of its time, Its speed vs an LA7 doesn't matter because it didn't fight against LA7s...   Its turn rate Vs a Hurricane doesn't matter because it didn't fight Hurricanes... It fought FW190's and BF109s... And against those planes it was superior in most aspects.  Just because some AHII 109 jock can whoop your butt when you're in a P51 doesn't mean the aircraft isn't capable of defeating a 109... It means you lost to that pilot... nothing more.

109s and 190s shot down lots of P51's... It was not like the sterile air wars of today where one team has an overwhelming advantage... winning by a few percent meant something...  Today if you lose 3 planes, something is wrong... That wasn't true in 1943.

It was not a perfect aircraft.  The F22 is not a perfect aircraft.  But it is still better than anything it is likely to fight.

The 51 had good speed, good agility, a good gun package, remarkable range, outstanding cockpit visibility.  It was a fighter pilots fighter much like the F16 today is a fighter pilots fighter.  It doesn't do everything, but it does most everything very well.

Find me a Spit or an LA7 that could fly from Britain to Berlin and back.

[Kurt]

Originally posted by F4UDOA
Agreed!! IMHO the peak of fighter design occurred in the 1950's. They may be better but they will never be as cool.  I love the B-58 Hustler.

In my school they taught us that 'B' meant Bomber.

Anyhow, all kidding aside, the hustler was neat, and it was fast.. But it was a joke as a bomber.  The big 'pod' being all you have...   Run in fast as hell, hope you don't get shot down... drop the nuke..

It was a short sighted machine with a short life to match.  There is a reason why the B52 is still flying today., and the Hustler is almost forgotten history.

The B58 was a machine to make the public feel secure... It wasn't a genuine war machine.  It would have been shot down by the thousands.  It was the one you put in the SAC window to say 'Yeah, we have supersonic nukes.'  It was nothing more than slick advertising by the Air Force.

[MiloMorai]

Originally posted by Nemeth
WOW what a poser! (and its all your base are belong to us)
i dont kno why ppl think the p51 was so good, a full fuselage tank made the plave VERY unstable in fights, with the amount of gas its held, it would blow up from only a few bullets, yes the speed is good.

But when ppl say the mustang won the war, they are wrong... its not the plane that won the war, its the people who flew the planes, the people that built the wepons, the vehicles, the botas and the planes, AND MOST OF ALL, the people that fought the war, both the people that survived and died.

If u want to argue me about this go ahead, HTC will prob lock this if 2 many peole do.

Sure the P-51 was VERY unstable.  That is why during Bodenplatte, a squadron of P-51s took off with full tanks, with drop tanks, while under attack and cleaned the air of LW a/c, all at low level. Not one crashed because of its fuel load. There was an aft CG bias but the a/c was still flyable, one just had to be careful about radical manuevers.

Yes people are wrong for it was the P-47 that did all the hard work. The P-51 showed up in the middle of the 3rd quarter to finish the job.