Wing Loadings

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the lancaster kicks ass

Major General
19,937
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Dec 20, 2003
Can you post any wing loadings of planes you know please, hopefully we can get a list together............
 
Heres some....

Bristol Bulldog IVA----------12.6 (306 sq. ft)
Polikarpov I15bis------------15.7 (243sq. ft)
Polikarpov I16 type 6-------23.5 (156sq. ft)
Fokker D.XXI-----------------26.0 (174sq. ft)
Polikarpov I16 type 10------24.2 (156sq. ft)
Gloster Galdiator Mk.II------15.1 (323sq. ft)
Fiat G.50----------------------26.9 (196sq. ft)
Polikarpov I153 (M-62)-------17.7 (238sq. ft)
Polikarpov I16 type 18-------25.9 (156sq. ft)
Morane Saulnier MS.406------31.7 (172sq. ft)
Arado Ar240-------------------330kg/m²
Messerschmitt Bf108---------87.5 kg/m²
Messerschmitt Bf110---------173 kg/m²
Heinkel He111----------------129 kg/m²
Focke Wulf TA152H------------202.1 kg/m²
Heinkel He219------------------305.4 kg/m²
Messerschmitt Me163B-1-----213 kg/m²
Focke Wulf FW189-------------103.9 kg/m²
Junkers Ju88-------------------161.1 kg/m²
Junkers Ju188E----------------258.9 kg/m²
Junkers Ju288B----------------324 kg/m²
Blohm Voss BV141----------60.2 kg/m²
Fieseler Fi156-------------------48.5 kg/m²
Mitsubishi A5M-----------------93.7 kg/m²
Mitsubishi J2M5-----------------174 kg/m²
Nakjima Ki44-IIB---------------200 kg/m²
Nakajima Ki84-Ia--------------172 kg/m²
Mitsubishi Ki67-Ib--------------208 kg/m²
Nakajima B5N2----------------101kg/m²
 
The less you have, the better is. Higher wingload often limits the agility of the plane. But for a general statment you have to take powerload into calculations, too.
 
delcyros said:
The less you have, the better is. Higher wingload often limits the agility of the plane. But for a general statment you have to take powerload into calculations, too.

Umm... lower wingloading tends to improve climbrates and turn rates. It can adversley effect "agility", making a plane roll sluggishly. In general, at lower speeds low wingloading is good, at higher speeds however you do not want as low a wingloading figure - a higher wingloading implies less drag. There is an optimal wingloading for a given speed range to balance turn/climb vs roll and quickness of response.

=S=

Lunatic
 
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Above wing loadings are excerpts of the chart below (entire PDF found here: F4U performance report and comparisons ).

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Wing loading has a lot of implications. Wing loading is expressed in pounds per square foot of kilograms per square meter.

Also, 1 lb/sq ft = 4.882 kg/ sq m or 1 kg/sq m = 0.2048 lb/sq ft.

The loading tells us how much weight is being lifted per square foot (meter) of wing surface. The area includes the fuselage area of the wing in general. WWII fighters ranged from a low of about 25 lbs/ sq ft to a high in the 45 lb/sq ft range. Higher meant a larger turning circle in general, but not specifically since the lift is related to the aerodynamic coefficient of lift rather than the area.

the thing is, all WWII designers were tying for the best fighter, and their coefficient of lift variance from one another was not all that great, so wing loading is a very good yardstick of maneuverability, though not always strictly correct. Early Spitfires were in the 25 psf range. The Bf 109 was in the 38 psf range, but had automatic slats that helped 1/3 of the wing generate more lift. The intention of the Bf 109 slats, however, was NOT more lift, but to keep the ailerons effective in the stall. They DID that.

Bombers were much more heavily loaded than fighters, and their span loading was probably more important than wing loading as they weren't trying to turn with the fighters anyway. A bomber Mosquito at 18,100 lbs was in the 39 psf range, close to the lesser-turning fighters, and better than some. But it wasn't a true fighter in any sense of the word, regardless of intent. Did they HAVE a fighter-bomber version? Yes, but it wasn't a day fighter that could live in a fighter environment. It was more of a fighter of opportunity.

Low wing loading also implies decent climb, even though power loading will affect that a LOT. Call it "high rate of climb for the installed power level." Generally, if the wing loadings of two fighters were close and power loadings were close, they were quite evenly-matched, assuming decent planes and pilots. What constituted "close" can be debated endlessly. I'd say if the wing loadings were within, say, 5 psf of one another and the power loadings were not more than 10 - 15% apart, they were close. If the power or wing loadings were farther apart, then the lower wing-loading, higher weight to power ratio was "better," whatever that means. Generally, to me, it means that with equal pilots, the "better" plane would usually, but not always, win. A lot depended on luck and whoever else was flying about with ammunition remaining and feeling friendly toward YOU.

Higher power loading usually means better acceleration and climb. SHOULD mean higher top speed, but does not always mean so due to a variety of reasons.

Span loading (pound per foot of span) generally affects higher-altitude operations. Lower span loading means better margin way up high. Again, not always, but generally.
 
Just to think about:

1) The best wing loading is when the aircraft has minimal fuel to run the engine and no ammunition. But, then it is useless for combat.

2) The worst wing loading is when you are at max takeoff weight, but nobody fights at that weight.

3) The wing loading usually quoted is at normal takeoff weight.

4) Wing loading usually seen in combat was at normal weight minus 1/3 internal fuel load unless you were carrying tanks. Then, you wing loading was at normal weight minus a few pounds for oil used.
 
Quoting or believing Wing Loading in comparison, or as a 'standard', is useless unless the boundary conditions are stated.

For example, there is in '50% loading standard'. 50% of what? Max Gross Weight? 50% of Internal fuel, oil and ammo?

IMO a (not The) standard is fully loaded combat weight, no external tanks or ordnance. That would give you a W/L at take off and more indicative of the design factors. For those that dive deeper than a published table with no context, such as reviewing FlightTest data, always seek the Description to note the pilot's observations of the aircraft and test conditions. Otherwise perform your own calculations with a range of assumptions.

Foe example a fully loaded P-51B/C with 100% internal fuel, ammo and oil - (269gal fuel) has a Take Off Gross weight of ~ 9700 lbs. S= 233.2 ft^2 WL= 41.6.

At long range, with fuse tank burned down (85 gal) and only 180 gal (some burned in left wing during warm up and take off) the Gross Weight is 9166 lbs (9700- 85(6)-4(6)) minus the weight of several gallons of oil.. basically 9100lbs. So, now the W/L =9100/233.2 = 39.6 #/sf which makes it much more nimble(than at takeoff) in comparison to 109 and 190 whose fuel fractions are lower.
 
I've seen charts which give the "normal" weight as full combat load at 50% fuel.
Such descriptions are as vague as 'Fighter Weight' or "Fighter Bomber Weight'. The manufacturer frequently presented categories are a. Empty Weight, b. Basic Weight and Maximum Gross Weight. When being flight tested the test pilot specifies the load out but there was/is no precise definition for 'Normal'.

Example: a load out for a P-51B might be a.) full wing tank internal fuel, b.) full ammo and c.) full oil. In this case the range potential is below maximum range and the airplane does not need 'full oil' - but practically oil tank is filled every mission as SOP. Extend mission profile to attach 75 gal external combat tanks. Still not close to Max Gross Weight.

Dean did an excellent job filing tables for manufacturer specific 'nomenclature' but when comparing fuel fractions between Fighter, Fighter Bomber, Max Gross, etc there were no examples of 50% fuel for internal tankage - all were closer (but not exact) to 70% internal fuel for 'Fighter' designation.
 
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Max gross weight is takeoff weight. Well, there's max overload, but once you fire up those engines and start rolling down the runway, your fuel and oil burn is going to reduce your weight. By the time you reach the target, where you can expect some opposition, the fuel and oil burn is going to reduce you to about %50 fuel.
Not counting bullets, the variable weight for a US medium was about 10,000 lbs of fuel and bombs.
 

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