A/C and drop tanks // data

[wernerpruckner]

Conditions ( from AAF Proving Ground at Eglin data)

a)
Warm-up and take off at 10 minutes at normal power

b)
Climb to 10k feet at normal rated power

c)
Cruise to target at 200mph (P47) 220mph (P38 and 51)

d)
Jettison drop tanks at target

e)
5 minute combat at war emergency power and 15 minute combat at military power

f)
cruise back to base at 10k feet at 210mph ( P47 ) and 230mph (P38 and 51)

g)
no account for decreased fuel consumption during descent

h)
Allowance made for 30 minute reserve fuel at minimum cruising power

i)
No allowance made for formation flight or evasive action other than 20 minute combat




(uw)...underwing
(cl)...centerline

[wernerpruckner]

P-38L

clean ( only internal fuel = 410 US gal.): 290 mile radius

with:
1x 1000lb (uw) bomb + 1x 165 US gal. (uw) external fuel : 400 mile radius


2x 500lb (uw) : 260 mile radius


2x 1000lb (uw) : 250 mile radius


2x 165 US gal external : 600 mile radius

[wernerpruckner]

P-47D

clean: ( only internal fuel = 370 US gal.): 280 mile radius


1x 108 USgal (cl) external fuel : 400 mile radius


2x 500lb (uw) + 1x 108USgal (cl) : 360 mile radius


2x 500lb (uw) : 260 mile radius


2x 1000lb (uw) : 230 mile radius


2x 150US gal (uw) : 575 mile radius

[wernerpruckner]

P-51B/C/D:

clean: ( only internal fuel = 269 US gal.): 350 mile radius


2x 500lb (uw) : 325 mile radius


2x 75 USgal (uw) : 650 mile radius


2x 108 USgal (uw) : 750 mile radius

[Hard Sarge]

Strange info, as it is not good for combat

they didn't fly at that cruise speed or at that alt ????

fine for training, but not combat

did they say which P-47 D they were using ?

[wernerpruckner]

Hi HS,

at least it is compareable data ( which is not very often when you look through testing reports)

Werner

[Denniss]

http://home.att.net/~jbaugher1/oldseriesfighters.html

Tons of info, not perfect but covers most USAAF aircraft

[Hard Sarge]

good site

Swift
I understand and agree

but still range and speed at 10 K is not the same as it would be at 20-25-30 K

(ahhh, I wish I still had a book group I had when I was a kid, it had range and max speed break downs for each plane, sea level, 1000, 5000, 10000, 15000, 20000, and 25000, and then what it;s best alt was for speed, in fact , it is one of the only book (they had one for each nation) that I have seen that did so)

(like the one I was just reading, a 1000 mile range at 195 mph, don't tell us anything worthwhile)

[Nikademus]

lol.....i'd heard that trying to reach a consensus on an aircraft's actual combat range was (is) probably the hardest thing to achieve. I wrestled with this in regards to the Spitfire Vb/VIII/IX/Hurricane in the latest version of my WitP mod and eventually just had to er... "wing it" and go with what felt like a decent generalization.

drop tanks.....fuel conserving and altitude....OH MY!

[Hard Sarge]

roger that

what I was doing with my talks with JC, was going by the missions that were flown and on what date

say if the plane type only could fly to Rottenhumburville, great, then on the 43rd of march, they flew a mission to Hamenrottenburg, which was 50 miles deeper then they had flown before and they just happened to be using the new drop tank for the first time

we can kind of say, hey, they got to be able to at least fly to here when they get the new tank type

which I got a hassle with the idea of the P-51 which flew missions into Poland, not being able to reach Berlin

[Speedysteve]

Agreed. The whole issue of flight radius is in many ways tough to be sure since different tests will occur in different conditions/weather/fuel type/condition of the engine/plane etc etc

It's nice to work in IT sales where there are certainties. NO that Camera has a maximum resolution of 6.2MP I assure you.

Steven

[Nikademus]

well admitedly for me, from my viewpoint, it was easier because anything beats having a plane only good for point defense just as with the old Ki-27 values. yukko. [:@]

win win situation

[HMSWarspite]

ORIGINAL: Hard Sarge

Strange info, as it is not good for combat

they didn't fly at that cruise speed or at that alt ????

fine for training, but not combat

did they say which P-47 D they were using ?

This data looks as though it is idealised mission data (a stylised FB mission). Today it would be a design mission profile ('we're not sure quite how we will use it, but make it do at least this'). In the test cases above, it it obviously a datum comparison mission. They probably didn't fly it literally, but would fly the various segments (except the cruise, where they would use spot consumptions and average them - no computers remember!). You then add the elements up. This would explain the 'no allowance for reduced fuel cons in the descent' - probably didn't bother to work that out (not a huge effect!). These days, you do the same job, but would use a computer to model the engine and fuel consumption, and then fly the mission on the computer (and several others, since it is so easy).

Of course, we don't know the state of the a/c and engine used. Off the line? Beaten old wreck? Old wreck with new engine? If this was even and average new a/c or engine (i.e. not specially prepared) there would still be factors applied to set the range that they should actually fly to in service to avoid the old wrecks not making it!

Of course (if the game code allows for fuel cons this precisely), it does actually give a (ideal?) range at 10000ft, and these speeds. However, the best way of using data like this (other than carefully!) is as a sanity check of relative ranges with loads/drop tanks etc gained from other sources (like who flew to where, with what, and were people diverting for fuel on the way back), as someone said above.

Whilst I am on the subject, how does the game do fuel cons with altitude? Crude steps? A curve? Datum plus some form of correction with alt?

[Denniss]

AFAIK the game does not alter speed or fuel consumption per altitude - it's always the sam cruise/max speed and fuel consumption regardless of altitude. That's one of the design limitations it has. Maybe the climbrate is decreased by altitude but I can't verify this without knowing details of the exe.

[harley]

Dennis - it's worse than that. The twin engine aircraft with DT/s use fuel at the same rate as single engined aircraft. It looks like the DT's were calibrated for 2 Gallons a minute, wheras most SE aircraft cruised around 1 Gallon per minute.

I know it's not fair to generalise, and as the details werner posted show, there was some considerable wastage, but having the same benefit regardless of engines is bad...