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renrich said:
drgondog, I could not find my handloading manual that had the ballistic coefficent of the .50 BMG bullet but online I found a Hornaday 750 grain bullet in .50 BMG that has a BC of 1.050, SD of .412. I had in my memory a BC of around .700 for the .50 BMG so I believe the Hornaday bullet validates that. I do believe the military bullets used in WW2 would have the .50 BMG with twice as good a BC as the 150 grain cal. .30 bullet. I also believe that the effective range of the .50 BMG is substantially greater than the 300 yards mentioned earlier by someone else.
Click to expand...

Renrich - I saw the Lilja article and still don't believe 1.050 for BC. I believe without proof that the form factor for the bullet would have to something like an area rule wasp waist to achieve that much improvement.. Of course my belief may be totally wrong!

Here is a link to one I do believe ~ .65 for the 668gr API which would be 50+% better than the 150gr ball round in the 30-06. The Hornady .50 BMG AMax has about the same form factor as the 7mm 170gr Amax so the comparative difference should be mass to mass divided by the diameter squared.

750/ .510>>2 compared to 170/.284>>2-------> 50 BMG AMax about 37% higher than the 7mm AMax in a very rough comp - which puts the very best .50BMG in the .7 BC range - not 1.050. Still awesome.

AmmoGuide is now... "Interactive"!

Anyway - the 50 cal being aimed by a K-14 would be very dangerous at the 800yd limit (theoretical) of the K-14 gunsight - well beyond the boresight range for convergence on either an F4U or P-51 or P-47.
 
Years ago, I started to make a simple DOS-program, allowing basic estimates on ballistics (both, interior and exterior), the details of recoil (not of importance here) and some approximations on typical barrel length, breech mechanisms and service lifetime (also, not important-and not concluded in this program-I dropped attention as a friend provided me with a more perfectual software).

It is based on approximations given at Tony Williams gun site and my data files for 278 ww1 ww2 guns projectiles.

The WWII Fighter Gun Debate: Gun Tables

here is what comes out:
MG 151/20 firing 105gramm projectile at 725 m/s muzzle velocity (at a given form factor of 1.67, attributed for very pointed but not boat tailed, derived from drawings): sec. density: 0.373275; bc: 0.623369
0.50BMG firing a 43.3gramm projectile at 880 m/s muzzle velocity (at a given form factor of 1.95, attributed for very pointed, full jacket boat tailed, derived from drawings): sec. density: 0.379106; bc: 0.739257


Everybody should now be able to do the maths on his own...

BTW, as noted already above by Kurfürst, the discussion about this detail is leading us nowhere...
 

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The info I quoted on the .50 BMG projectile was from a Hornaday website. Anyway, as others have observed we seem to be doing some hairsplitting but us hand loaders are good at that sort of thing. Keeps us awake at night sometime. Also, I believe the .50 cals used by all the air forces of the US in WW2 were a very effective weapon. The one time I fired one it made me feel invincible.
 
drgondog said:
The 15th AF did not get their Mustangs until May 1944. For example the 325th FG converted to P-51s in May.

The order was 9th AF first with 354th in December 1943, then the 363rd on Feb 23 1944...

The 8th received the 357th FG from the 9th and it started Ops in Feb 11, 1944.. then the 4th around the 26th, then the 355th on March 8 with one squadron, then the 352nd in early April, then 339th on April 30..

The 8th AF was very 'thin' on Mustands over the target until late August as both the 354th and 363rd returned to 9th AF operational control in May. By D-Day the 339th, 359th and 361st were all operational to pick up the 'vacuum.'

The 15th continued to fly a mixture of the P-38 and P-51 to end of war, whereas the last of the P-38 groups in ETO converted in late September (479th), while the 20th, 55th and 364th converted in late July
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Hi,

Thanks for this sort of info, I really appreciate it. I am almost totally ignorant on the subject, so bear with me if I ask some very basic questions :

1, Do you have some sorts of strenght breakdown, too? I mean something like

end of 43-Nov : zero Mustangs
end of 43 dec : say 100 Mustangs with operational units (all with 354th), 80 servicable
end of 44 feb : say 150 Mustangs with operational units (say 80 with 354th, 40 with 363rd, 30 with the 4th FG), 120 servicable in total

and so on ?

Basically what I am trying to achieve with these sort of data is to establish how availibilty and performance related.. quantity vs. quality, does the plane has both? I am trying to avoid fixation on rare, best variants (obviously the Mustang isn`t such) if at the given date would be available only in limited numbers, introduction of the Me 262 and P-51D in the summer of 1944 comes to mind... they are 'contemporaries', only that one has the numbers to make it`s performance felt in the air, the other doesn`t.

2 What`s the importance of being issued to the 9th, I though the 8th Strategic and 9th Tactical were on the same side of the fence. :D Or did the Army Air Force think different at the time...? Did the 9th strictly operated against targets in France or...?
 
Kurfürst said:
Hi,

Thanks for this sort of info, I really appreciate it. I am almost totally ignorant on the subject, so bear with me if I ask some very basic questions :

1, Do you have some sorts of strenght breakdown, too? I mean something like

end of 43-Nov : zero Mustangs
end of 43 dec : say 100 Mustangs with operational units (all with 354th), 80 servicable
end of 44 feb : say 150 Mustangs with operational units (say 80 with 354th, 40 with 363rd, 30 with the 4th FG), 120 servicable in total

and so on ?

Yes - but they are 'approximate' - just like the availabilty of LuftFlotte Reich in that timeframe. The first thing to recognize is that the basic TO&E of the USAAF Fighter Group was 72 'authorized' but the truth is that few Mustang Groups had more than 60-64 in the inventory until May-June 1944.

The second thing is that the Mustang was very tempermentl in Dec-May, 1944, requiring usually 8-10 spares to manage to get three sqadrons of 16 a/c at the target. In Dec-Mar most were lucky to get 40 P-51's escorting primarily because of engine related mechanical problems - mostly plugs, manifold pressure and coolant.


That said - I spent a lot of time on this while trying to educate Soren on the 'realities' of overwhelming air superiority by Target Escort fighters in Dec 1943 through May 1944. Remember that P-47s had to stop along Bremen to Stuttgart axis and served as Penetration and Withdrawal Escort until the P-47M finally gave them the range to go all the way. Only the Mustang and Lightning units could go all the way.


So, as we said before 'let's do the math'

Dec-Feb 11, 1944 - one Group (354)60+ on the base, 30-40 over target plus 20th and 55th FG P-38 units with 30-40 each

Feb 11, 1944 - two Groups (354 and 357), slightly better reliability, 70-80 over target plus 20th and 55th P-38 units of 30+ each over different targets

Feb 23-26 - four Groups over Taget (354, 357, 4th, 363rd) 140 Mustangs over different targets plus the two P-38 Groups

March 8 to April 10 - five groups over Targets (4th, 357th and 355th - 8th AF, 354th and 363rd - 9th AF) - ~190-200 Mustangs over different targets to escort Three Bomb Divisions of 35+ Bomb Groups attacking 1-8 different targets - At this time the P-38 groups also had three full strength units (20th, 55th and 364th).

April 10- April 29 - six Mustang (4th, 352nd, 354th, 355th, 357th and 363rd)and three Lightning groups over Targets - reliability up so each Mustang and P-38 group effectively averaged 40+ each at the target, P-51s slightly higher - P-38's slightly lower. The 479th FG came into ops as fourth and last P-38 group in 8th AF in early May

The 339th flew first missions as Penetration or withdrawal support from April 30 forward to mid May and the the 361st and 359th FG came into ops in mid May as the 354th and 363rd returned to 9th AF control in prep for D-Day.

So May had the same basic Constituency of six Mustang groups getting now closer to 45-48 ships each at the target for 270-288 Mustangs plus 200 Lightnings deep into Germany. It was in mid May that the 15th AF started coming on line with Mustangs.

May through September is the major conversion period in which every 8th AF FG except 56th, 78th, 353rd and 356th. The 78th, 353rd, and 356th converted in Oct-Dec 1944 to raise the number of Mustang Groups to 14. In October - rest of war each Fighter Group could and would put 60+ Mustangs in the air over target. This is the period in which large forces of Mustangs were flying at least three Sweeps out in front of Escorts looking for GAF fighters trying to form up and disrupt them - often with numerical advantage over the German fighters when they found them.

Hope this helps sort it out.

Basically what I am trying to achieve with these sort of data is to establish how availibilty and performance related.. quantity vs. quality, does the plane has both? I am trying to avoid fixation on rare, best variants (obviously the Mustang isn`t such) if at the given date would be available only in limited numbers, introduction of the Me 262 and P-51D in the summer of 1944 comes to mind... they are 'contemporaries', only that one has the numbers to make it`s performance felt in the air, the other doesn`t.

The variants for December were the P-51B-1 and -5 followed in January. The P-51B and C variants came into inventory as -5 and -7 in March timeframe along with factory installed 85 Gallon Tank plus start of field modification Malcolm Hood. In March the P-51 suffered troubling engine mount failures (inadequate heat treat - and quickly replaced) plus a couple of wing and tail failures traced to the uplocks failing on the main gear door causing the landing gear to drop at 450-600IAS with catastrophic results. Uplock kits and intro of P-51D in June solved that problem. The P-51B-10s and -15s arrived in April timeframe.

The P-51D-5 arrived in the late May, the P-51D-10 with tail strake and re-inforced tail mount structure arrived in July to solve (mostly) high speed yaw issues of new bubble canopy version. The 51D-20 with tail warning radar came into play in February time as well as first P-51H production models in US.

2 What`s the importance of being issued to the 9th, I though the 8th Strategic and 9th Tactical were on the same side of the fence. :D Or did the Army Air Force think different at the time...? Did the 9th strictly operated against targets in France or...?
Click to expand...

A curious choice. The 354th and 357th FG in 9th AF trained in P-39s and naturally were assigned the P-51 as in line engine extension but Eaker and Doolittle immediately 'borrowed' the P-51 in the form of the 354th FG and agreed to transfer the P-47 equipped 358th in exchange for the next P-51 Group, the 357th...They also worked out the exchange of the new P-38L's due to come to ETO in May for all the P-51s allocated to the 9th AF.

The 9th then committed to P-47, and even forced the 354th Pioneer Mustang Gp to convert in November until late Feb 1945 when they got their Mustangs back.

The 9th AF operated against France but also Lowlands and combined many operations w/8th AF to attack some strategic targets in western Germany, primarily with B-26s.

In 1943 the 9th AF B-26 and B-25 Groups would occsionally fly Penetrations at 20,000 feet to fool German Controllers into guessing whether they were B-24 Groups inbound to Germany - then drop lower to attack tactical targests inland from Coast to Koblenz for example. They were more frequently escorted by RAF than 8th as well as their own P-47 and later P-38 groups.

Their assignments were primarily tactical and focused on the Invasion and future tactical ops in front of INvasion force.

Regards,

Bill
 
Good discussion Bill and Kurfurst and good info Bill. I think everyone will find this discussion and info interesting.

As Bill said my :salute: to the SEAL.
 
I agree, good discussion and info provided by Bill Kurfürst.


Bill,

I agree with you on the Dora vs P-51 subject.

And :salute: to the fallen SEAL.

Well, maybe in your hands. It had severe low altitude deficiencies compared to some other late war aircraft, especially in speed and probably in climb
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Davparlr the Ta-152H-1 has a top speed of 597 km/h at SL, climb rate is above 5,000 ft/min, and 10km was reached in just 10.1min. Exactly which Allied piston engined fighter which saw active service during WW2 could match this ?
 
lesofprimus said:
I dont know why we are comparing the Dora-9 to the -51B in the first place, as I dont think the 2 ever met in the skies over Germany....

Soren, as far as I can determine, no Allied fighterr could match the numbers of the 152H-1...
Click to expand...

Les - actually the D-9 probably did tangle in a very limited way against some 51B's. Both the 353rd and 78th FG were converting from Jugs when the Dora started rearing its ugly head and both were receiving some 51B/C's from different Groups already equipped with D and K's. A lot of the Recon units were still flying B's as well as RAF

I would have to look at the order of battle for both the 355th and 78th for January 14, 1945 but the 78 hurt JG26 Dora's near Koblenz and the 3554FS/355 hurt another unit a little further north near Munster - just for two possibilities.

Future test pilot and 355th vet (again) of Vietnam, Bob White was shot down in WR-V 42-103795 P-51C on Feb 23rd, 1945

I would estimate that most of 8th FC command still had 10+% P-51B in Nov/Dec 1944 timeframe.

Dad's 355th had at least 5 of the P-51B/C's still flying combat in April 1945. It wasn't until VE Day when deployments were planned to Germany that all the groups finally got full 51D TO&E.

He actually preferred the B w/Malcolm Hood to the D as the pure 'gunfighter' as he felt it turned better and accelerated better than the D at mid to high altitude (anecdotal recollection) - and it was faster at altitude..

It's an interesting question about P-51B versus Fw 190 Dora.. I can speculate but I don't KNOW.
 
I read somewhere that 1/3 of all P-51 in the ETO still had 4 MGs. I suppose this meant they were primarily P-51Bs as also some P-51Ds were equiped with just 4 guns. I expect only few P-51Ds had 4 guns but I could be wrong.

Or the notion that 1/3 had only 4 guns is wrong, that's also possible.

Kris
 
It's an interesting question about P-51B versus Fw 190 Dora.. I can speculate but I don't KNOW.
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Aerodynamics and the anecdotal evidence I've collected over the years supports your speculations as-well as the anecdotal evidence you've collected so far though Bill (If I've understood you correctly that is ofcourse)

According to its pilots the Dora-9 turned rolled better than the P-51, esp. at high speeds. But above 20kft the difference between these two fighters was minimal.
 
lesofprimus said:
I dont know why we are comparing the Dora-9 to the -51B in the first place, as I dont think the 2 ever met in the skies over Germany....

Soren, as far as I can determine, no Allied fighterr could match the numbers of the 152H-1...
Click to expand...

Dan - I have never been able to see all the flight test data on the F7F but have heard too many marine and naval aviator types swear that the a/c was "twice as good as the F6F" and preferred it to F8F.

I know that the best speed in the first production birds in late 1944 was 460mph at 21,000 and anecdotally that it had 'twice the climb" of the F6F which would put it in Ta152 spectrum below 30,000 feet and probably slightly better in medium to low altitudes - but I sure would like a pointer to a location that has facts instead of feelings on this subject.

Objectively the Ta152H-1 was the 'best' fighter designed and produced.
 
Agreed Bill, the F8F was a beast in the climb! (It was a beast at most things really)
 
Civettone said:
I read somewhere that 1/3 of all P-51 in the ETO still had 4 MGs. I suppose this meant they were primarily P-51Bs as also some P-51Ds were equiped with just 4 guns. I expect only few P-51Ds had 4 guns but I could be wrong.

That begs the question re: Timeframe. For, example, the D was introduced to ETO combat ops in Late May, 1944. By September 1 all of the 'original' Mustang units were probably 75/25 P-51D to P-51B/C.

The P-51B/Bs were also starting to 'wear' out with the first ones being retired as War Weary in June/July with a wave of them in December/January.

I know for example that the 4th and 355th FG received 'used P-51B-1 and -5's from the 354th and 363rd FG as they converted from P-47s in late Feb/early March, 1944 and those ships had 300+ hours on the airframe.

But complicating the issue was the 20th, 55th, 364th and 479th P-38 units converting to the Mustang in July-September. They received ALL of the last remaining P-51B-15 and P-51C-10s before they started getting their fair share of P-51D's.

All of the P-51D/K were shipped with six 50's but I know of some die hard pilots that wanted less weight and more ammo and had two removed. All of the P-51B/Cs were equipped with 4 Browning 50 Caliber MG

Or the notion that 1/3 had only 4 guns is wrong, that's also possible.

Kris
Click to expand...

Kris - Likely to be wrong on VE Day, but likely to be right in November 1944
 
Soren said:
Agreed Bill, the F8F was a beast in the climb! (It was a beast at most things really)
Click to expand...

Soren, the nagging thing is back to anecdotal stories.

One of my dear friends was a marine Night Fighter that flew F7Fs out of Okinawa at the end of the war. He flew F4Us, F7F and also flew the F6F and F8F. He swore that the F7F was the best single piston engine fighter he ever flew and I have heard this from several pilots that flew the F7F.

It was a 'beast' in a spin (unrecoverable after 3-4), a beast in a dive above .8Mach but allegedly outclimbed the F8F by a significant margin, was faster and could out dive it. Could not turn or roll with F8F.. but I want to see the facts (lol).

And the 'freakin' thing could carry a TORPEDO...try sticking that on a P-51 (or Ta 152)
 
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