Hypothetical Combat - P-38L or P-47N
- Thread starter Magister
- Start date
Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules
MP-Willow
Staff Sergeant
it is tough but could make a great flight! All that deep blue water to fly over 
Jabberwocky:
All data is from Republic performance tests under military conditions.
The P-47D-27 weighed in at 14,500lbs for combat gross weight.
The P-47N weighed in at 16,330lbs for combat gross weight.
Climb rate was:
2,950fpm at 5,000ft
2,600fpm at 15,000ft
1,600fpm at 28,000ft
The P-47M weighed in at 13,275 for combat gross weight.
Climb rate was:
3,775fpm at 5,000ft
3,425fpm at 15,000ft
2,375fpm at 28,000ft
If the P-47N was loaded up with a fuel load equivalent to a full load carried by the P-47D-27, the P-47N would weigh in at 15,130 lbs. (200 gallons less fuel)
Between the P-47D-27 and the P-47N, the P-47N would weigh 630lbs more, have 270 more horsepower and a wing area 22sq.ft. larger.
I think the P-47N would have a climb rate at 5,000ft of about 3,400-3,450fpm with a full "D" fuel load.
All data is from Republic performance tests under military conditions.
The P-47D-27 weighed in at 14,500lbs for combat gross weight.
The P-47N weighed in at 16,330lbs for combat gross weight.
Climb rate was:
2,950fpm at 5,000ft
2,600fpm at 15,000ft
1,600fpm at 28,000ft
The P-47M weighed in at 13,275 for combat gross weight.
Climb rate was:
3,775fpm at 5,000ft
3,425fpm at 15,000ft
2,375fpm at 28,000ft
If the P-47N was loaded up with a fuel load equivalent to a full load carried by the P-47D-27, the P-47N would weigh in at 15,130 lbs. (200 gallons less fuel)
Between the P-47D-27 and the P-47N, the P-47N would weigh 630lbs more, have 270 more horsepower and a wing area 22sq.ft. larger.
I think the P-47N would have a climb rate at 5,000ft of about 3,400-3,450fpm with a full "D" fuel load.
MP-Willow
Staff Sergeant
Nice numbers for the P-47. Now though how dose it compair to the P-38? I still think that the P-28 would have an edge, maybe not a big one but one.
wmaxt
Staff Sergeant
MP-Willow said:
From AAF Test 47-1706-A, P-38J (The Pilots Handbook uses the same number for the L and a Lockheed test shows they may even be a little better in the L) No. 42-67869 weight 16,600lbs (full internal fuel, early J, full ammo and 100lbs ballast.
SL - 4,000ft/mn
5,000ft - 3,960ft/mn
10,000ft - 3,820ft/mn
15,000ft - 3,550ft/mn
20,000ft - 3,190ft/mn - 5.37min
wmaxt
wmaxt
Staff Sergeant
R988 said:
The P-38 was more spread out and had an extra of everything. If it was ground attack missions over land I'd think about the P-47, if it over long stretches of water I'd choose the P-38. When a cylinder was shot out it meant extra oil was being lost, most of the time when a P-47 came home with that kind of damage it was 150mi or less, the reason radials had so much oil on board was the high usage of the engines. Oil consumption is a major factor in limitations of range in big radial engines even if there in perfect running condition.
BTW, The max roll rate of a P-47N is just over 100deg/sec at 250mph and goes down from there. At 250mph thats 30deg/sec more than the P-38 but about equal by 350mph.
wmaxt
Sal Monella
Airman 1st Class
"most of the time when a P-47 came home with that kind of damage it was 150mi or less,"
Where did this little gem of data come from?
At any rate, see the below excerpt from the Joint Fighter Conference posted on another thread by Magister:
------------------------------
P. 87
Colonel Garman: "I can speak only for the African theatre and only for a particular type of operation. The P-38 was used at low altitude on many occasions and we found that it was quite vulnerable to ground fire - any type of ground fire, even small arms fire. But other planes also experienced that same ground fore and the radial engines brought the planes home. You can't lay down any hard and fast rule and say the in-line engine is no good at low altitude as far as ground fire is concerned, It all depends on the operation entirely."
Lietenant Colonel Tyler: "We have data which shows that in the entire European theatre the P-47 is much better able to take punishment and return after any sort of mission - either ground attack or any mission which incurs damage. That may be due to the P-47 airplane or due to the air-cooled feature. We don't know which, but it certainly can take it better than other types."
Where did this little gem of data come from?
At any rate, see the below excerpt from the Joint Fighter Conference posted on another thread by Magister:
------------------------------
P. 87
Colonel Garman: "I can speak only for the African theatre and only for a particular type of operation. The P-38 was used at low altitude on many occasions and we found that it was quite vulnerable to ground fire - any type of ground fire, even small arms fire. But other planes also experienced that same ground fore and the radial engines brought the planes home. You can't lay down any hard and fast rule and say the in-line engine is no good at low altitude as far as ground fire is concerned, It all depends on the operation entirely."
Lietenant Colonel Tyler: "We have data which shows that in the entire European theatre the P-47 is much better able to take punishment and return after any sort of mission - either ground attack or any mission which incurs damage. That may be due to the P-47 airplane or due to the air-cooled feature. We don't know which, but it certainly can take it better than other types."
wmaxt said:
And coolant is a major factor in the P38, the cooling system in most water cooler types was very vunerable to small arms fire, also the turbo plumbing is very vunerable as well. Wont get very far with the cooling system damaged any more than a radial losing oil. Though if you are lucky at least one engine might survive damage and be able to get you home. Unless you're carrying Sturmovik levels of armour, inline engines are generally regarded as more vunerable to small arms fire than radials.
Sal Monella
Airman 1st Class
"The P-38 was used at low altitude on many occasions and we found that it was quite vulnerable to ground fire - any type of ground fire, even small arms fire. But other planes also experienced that same ground fire and the radial engines brought the planes home."
The implication of the last sentence is that single engined radial aircraft could make it home where double engined in-lines could not under circumstances where "that same ground fire" was experienced.
The implication of the last sentence is that single engined radial aircraft could make it home where double engined in-lines could not under circumstances where "that same ground fire" was experienced.
wmaxt
Staff Sergeant
Sal Monella said:
I got that from reading accounts of these situations, NOT from any particular source. It was a while back but there are at least two books dedicated to this subject. Sometimes as many as 6 cylinders were shot out and the aircraft still came back. Serious ground attack in the ETO began began in late April, '45 and concentrated in France, roughly 100mi from the English coast. Once ground bases were available on the continent the P-47s and P-38s flew from those, most of these flights were less than 100mi radii. Everyone who ran out of oil went down.
Sal Monela said:
First, if you check my post you will see that I broke it out on a mission basis, ground attack being a condition that I would at least consider the P-47 (depending on mission).
Yes the P-38 was a bit more susceptible to ground fire. The turbo ducting isn't a big deal unless you need full power suddenly but a hole in the cooling sys is an issue. I know of one story where a P-51 was hit in the cooling sys just South of Berlin. The pilot pumped primer into the engine to help cool it, and nursed it back to England!!
Statistics are deceiving, for instance the P-38 faced combat almost every time it went out. The P-38 was also outnumbered for the majority of its missions in Germany. In Dec. '43 there were 380 P-38s total maybe 250/275 went on deep missions into Germany, There were 1,215 P-47s available to do the initial/final escort into mid-France. The shorter range P-47s that escorted on these missions often and consistently reported no contact but could see the Luftwaffe fighters just outside there range waiting to attack. These sorties accounted for about half the P-47 sorties in the ETO, because they often did two of these in one day and they did them in mass. Taking that into consideration that evens out the overall loss to sortie rate a lot.
Something else that needs to be considered is the mission. A hard target will need massed firepower and a heaver bomb load, the P-38 is probably a better choice and its heaver ordinance load means fewer passes, meaning less overall risk. The P-47 with its wider spread of fire and lighter load ability would be better on troops, convoys etc, its resistance to small arms fire is a bonus.
wmaxt
wmaxt
Staff Sergeant
R988 said:
Yep, If you check I said that if I was going to do ground attack Id at least consider the P-47 (depending on mission/target).
If I'm air to air below 30,000ft I want the P-38, especially if I'm over water. If I'm doing ground attack against a hardened target, or ships or similar target, I want the P-38, but if that target is spread out like troops etc. the P-47 would probably be a better choice.
wmaxt
Sal Monella
Airman 1st Class
Indeed you did break it down:
"If it was ground attack missions over land I'd think about the P-47, if it over long stretches of water I'd choose the P-38."
However, if a plane makes it back, it makes it back whether having flown over water or land. The quote from Lieutenant Colonel Tyler said, "...the P-47 is much better able to take punishment and return after any sort of mission - either ground attack or any mission which incurs damage."
The operative portion here is "any sort of mission." They collected data. They actually looked at different sorts of missions and concluded that "the P-47 is much better able to take punishment and return after any sort of mission - either ground attack or any mission which incurs damage."
I am puzzled by your preferencer of the P-38 over water. The advantage is purely psychological. Why would we conclude that if the P-47 had to fly back over water, as opposed to land, that it wouldn't make it back or conversely, if the P-38 had to fly over water as opposed to land, that it would make it back?
Making it back entails the abilty to maintain controlled flight. It matters not if the surface beneath you is water or land.
Additionally, there is no data to support the notion that the P-47, with its single radial engine, was less mechanically reliable than the two in-lines in the P-38. In fact, P-38's were grounded due to engine problems much more frequently than P-47's in the ETO. It was not uncommon for P-38's to turn back after beginning missions due to engine problems.
Having two engines also means that there's twice as many engines for mechanical failure to strike. If there is a problem with one of the engines, the pilot will wish he had a plane with one reliable engine working at full capacity. A single engine fighter at full capacity is better than a twin engine fighter with one engine at 80% capacity.
"If it was ground attack missions over land I'd think about the P-47, if it over long stretches of water I'd choose the P-38."
However, if a plane makes it back, it makes it back whether having flown over water or land. The quote from Lieutenant Colonel Tyler said, "...the P-47 is much better able to take punishment and return after any sort of mission - either ground attack or any mission which incurs damage."
The operative portion here is "any sort of mission." They collected data. They actually looked at different sorts of missions and concluded that "the P-47 is much better able to take punishment and return after any sort of mission - either ground attack or any mission which incurs damage."
I am puzzled by your preferencer of the P-38 over water. The advantage is purely psychological. Why would we conclude that if the P-47 had to fly back over water, as opposed to land, that it wouldn't make it back or conversely, if the P-38 had to fly over water as opposed to land, that it would make it back?
Making it back entails the abilty to maintain controlled flight. It matters not if the surface beneath you is water or land.
Additionally, there is no data to support the notion that the P-47, with its single radial engine, was less mechanically reliable than the two in-lines in the P-38. In fact, P-38's were grounded due to engine problems much more frequently than P-47's in the ETO. It was not uncommon for P-38's to turn back after beginning missions due to engine problems.
Having two engines also means that there's twice as many engines for mechanical failure to strike. If there is a problem with one of the engines, the pilot will wish he had a plane with one reliable engine working at full capacity. A single engine fighter at full capacity is better than a twin engine fighter with one engine at 80% capacity.
FLYBOYJ
"THE GREAT GAZOO"
Sal Monella said:
It been proven that multi-engine combat aircraft (I'm talking 2 engines) generally have a better survival rate than single engine aircraft - with that said, it's also been proven that a multi engine aircraft is more dangerous to the "rookie" and is more of a hazard when loosing an engine on takeoff. In a single engine aircraft, if you loose and engine on takeoff, you know you're going down - in a twin, you loose an engine, you think you'll make it but chances are you'll just go down a little further...
Remember when Yamamoto was killed? That particular mission, flown by the 339th, was labeled "SQUADRON 339 P-38 MUST AT ALL COSTS REACH AND DESTROY. PRESIDENT ATTACHES EXTREME IMPORTANCE TO MISSION." The planes were in tip top condition to be able to carry out this critically important mission. Even so, they had more than 10% of their flight turn back due to "engine problems."
Until the J model the problems were pretty bad.
http://home.att.net/~ww2aviation/P-38.html
Many of the P-38's assigned to escort missions were forced to abort and return to base. Most of the aborts were related to engines coming apart in flight. The intercoolers that chilled the fuel/air mixture too much. Radiators that could lower engine temps below normal operating minimums. Oil coolers that could congeal the oil to sludge. These problems could have been fixed at the squadron level. Yet, they were not. It took the P-38J-25-LO and L model to eliminate these headaches.
http://bob.hentges.lu/articles/en/p38.html
The Allison engines of the Lightnings proved to be somewhat temperamental, with engine failures actually causing more problems than enemy action. It is estimated that every Lightning in England changed its engines at least once.
The powerplant problems were not entirely the Allison engine's fault. Many of the reliability problems were actually due to the inadequate cooling system, in particular the cumbersome plumbing of the turbosupercharger intercooler ducting which directed air all way from the supercharger out to the wingtips and back. In addition, the lack of cowl flaps were a problem. In the European theatre of operation, temperatures at altitude were often less than 40 degrees below zero and the Lightning's engines would never get warmed up enough for the oil to be able to flow adequately. Octane and lead would separate out of the fuel at these low temperatures, causing the Allisons to eat valves with regularity, to backfire through the intercooler ducts, and to throw rods, sometimes causing the engine to catch fire.
These problems bedeviled the Lightnings until the advent of the J version with its simplified intercooler ducting and the relocation of the oil cooler to a chin position underneath the propeller spinner. When the P-38J reached the field, the Allison engine was finally able to attain its full rated power at altitude, and the engine failure rate began to go down.
Until the J model the problems were pretty bad.
http://home.att.net/~ww2aviation/P-38.html
Many of the P-38's assigned to escort missions were forced to abort and return to base. Most of the aborts were related to engines coming apart in flight. The intercoolers that chilled the fuel/air mixture too much. Radiators that could lower engine temps below normal operating minimums. Oil coolers that could congeal the oil to sludge. These problems could have been fixed at the squadron level. Yet, they were not. It took the P-38J-25-LO and L model to eliminate these headaches.
http://bob.hentges.lu/articles/en/p38.html
The Allison engines of the Lightnings proved to be somewhat temperamental, with engine failures actually causing more problems than enemy action. It is estimated that every Lightning in England changed its engines at least once.
The powerplant problems were not entirely the Allison engine's fault. Many of the reliability problems were actually due to the inadequate cooling system, in particular the cumbersome plumbing of the turbosupercharger intercooler ducting which directed air all way from the supercharger out to the wingtips and back. In addition, the lack of cowl flaps were a problem. In the European theatre of operation, temperatures at altitude were often less than 40 degrees below zero and the Lightning's engines would never get warmed up enough for the oil to be able to flow adequately. Octane and lead would separate out of the fuel at these low temperatures, causing the Allisons to eat valves with regularity, to backfire through the intercooler ducts, and to throw rods, sometimes causing the engine to catch fire.
These problems bedeviled the Lightnings until the advent of the J version with its simplified intercooler ducting and the relocation of the oil cooler to a chin position underneath the propeller spinner. When the P-38J reached the field, the Allison engine was finally able to attain its full rated power at altitude, and the engine failure rate began to go down.
wmaxt
Staff Sergeant
Jank said:
There were some problems These were the major problems, sources and related info as I see them:
1. The P-51 had the same abort rate of 30% initialy, the problems on both planes were pretty much solved by March, '44. The Js were being introduced as early as Feb.
2. "All those Problems" in the 8th AF. The 8th AF lost 451 P-38s to all causes total including mechanical problems. The sortie/loss ratio in the 8th AF was actualy about 1/2 that of the Mustang.
3. Art Hieden flew 300+ hours without a single problem with his engines, and he's not the only one. Art Stressed that if you ham handed it you could have problems but not if you operated them correctly.
4. They had no problems in the Aleutions where the temp on the Ground was -40deg.
5. Many pilots ran with oil cooler doors in 'manual open' when the Js arrived.
6. Cruise settings used in the ETO were often 2400rpm and low boost pres. causing the engine oil to solidify and the exaust to turbo piping to be cool not giving the pilot any heat. Using 1800rpm and 34" boost like they did in the Aleutions kept things warm.
7 the intercoolers were a problem, not enough capacity for later engines, F on, causing detonation if to much boost was used to long. If the fuel wasn't mixed properly, and at first it wasn't, it could seperate the lead, causing detonation.
jank said:
Sorry, I got ahead of myself a little. Your basically right here but there were some additional issues that I posted above. Tn the J the oil cooler was always in the chin but they did enlarge it, it was the intercooler that made the chin bigger and it did simplify the ducting a lot.
Another thing thats rarely mentioned, the P-38s were based around Kings Cliff and as far as 100mi from the coast while the other fighters were near the coast.
wmaxt
