Qualities that made for a great aircraft that don't show up in performance stats.

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That is so, but even with the single stage charger, Pratt's altitude performance was better.
Cheers,
Wes

The 1942-44 vintage R-2800 was making 100 rpm more, and had 200 cu in more, so yes, it is normal to have more HP all-around. Above 13500 ft, some 15% more - at 15000 ft, it was ~1550 HP for the R-2800 and ~1310 for the R-2600; all for 1-stage engines, military power.
 
I don't know much about the earlier invasion of Saxons and Angles but the followup to the Norman invasion was quite brutal, thorough and harsh - more so than tends to be discussed in the popular versions of the history. The Normans were not nearly as 'easy going' as the Norse settlers had been by comparison. And the courts (legal and courtier) were still largely speaking French 200 years later.

Speaking of which there is also the intervening layer of the Norse, as another thing which seems to get glossed over was the Danelaw in the north centered on York and then later the total conquest of England and reign of the mighty but little known Canute the Great which lasted from 1018 until 1035. There were various warlords contesting who would be top dog after that, and certainly some were Saxons, but the Normans were in part taking over from a Anglo-Norse ruling class in 1066.

One other thing, I'm not sure who deserves credit for it, but England had undergone a certain amount of proto- industrialization prior to the Norman invasion. Their survey of assets a few years after Hastings, the domesday book (completed under orders of William the Conquerer by 1085) indicated something like 5,000 water mills around the country which was pretty good for that time.

But for whatever reason, maybe due to the rule of the Normans, England seems to have fallen behind in terms of mechanization and industrialization by around the 12th Century, and remained in catch up mode for most of the middle ages, exporting huge amounts of raw wool and having to import most of their technologically advanced goods like metal tools, armor and ship fittings, textiles and so forth, from Flanders, Italy or Germany. Internal and external wars (100 yrs wr and War of the Roses) pre-occupied the English monarchs for much of the Late Medieval period and it really wasn't until the reign of Henry VIII that their textile industries caught up.
 
I don't know much about the earlier invasion of Saxons and Angles but the followup to the Norman invasion was quite brutal, thorough and harsh - more so than tends to be discussed in the popular versions of the history. The Normans were not nearly as 'easy going' as the Norse settlers had been by comparison. And the courts (legal and courtier) were still largely speaking French 200 years later...
For what it's worth, my Saxon ancestors were against the Normans and more particularly, my ancestor Henry Lilley fought alongside King Harold at Hastings.
 
I was thinking since this topic didn't explicitly cover just fighters, but all aircraft (or at least combat aircraft), it seems that there are traits that are good for all aircraft, as well as traits that are specifically good for fighters, dive-bombers, level-bombers/torpedo-bombers, correct?

For any aircraft, I assume useful traits would include
  1. Properly equipped for the mission at hand
  2. Ease of handling
    • Aircraft
      • Control forces should not be too heavy or light
      • Control forces should be harmonized so that if the elevators are light, so too should the ailerons and rudders
      • Control forces should be easily modulated, so a pilot can very easily achieve the desired g-load, and roll-rate for a given speed.
    • Engine
      • Easy to adjust settings without too much effort
  3. Human-factors/ergonomics
    • Basically, everything should be laid out in a fashion that is intuitive, and easy to find and access: Things should not be put in odd locations that nobody would think to look.
  4. Maintainability
    • The aircraft should not be difficult to maintain
    • It should be able to be maintained quickly allowing good readiness

BTW: I would normally quote things but everytime I do, fubar57 fubar57 loses his cool and leaves the thread, so I'll just try and keep it on topic
 
The topic is Qualities that make for a great aircraft that doesn't show up in performance stats, not useful traits in a aircraft.

If the aircraft is too sensitive to fly except by the most skilled, that will certainly be remarked on in the stats. If it's too sluggish that will also be noted.

If it's not equipped for it's intended mission, someone will take note also.

Etc. etc.
 
tyrodtom said:
The topic is Qualities that make for a great aircraft that doesn't show up in performance stats, not useful traits in a aircraft.
Under the criteria, you listed -- there would be no traits that would not be listed.

The fact is, at the start of the thread -- and I have read it from start to finish (with a bit of glaze-over in the middle) -- and the F6F was cited as an example. It's performance didn't look too extraordinary, but it was an amazing aircraft.

The reasons were that
  • Handling qualities were easy to master compared to the F4U
  • Stall characteristics were docile and aileron control was retained through much of the stall and lead-up
I would also add that
  • Many carrier planes were naturally at a disadvantage when it came to speed because of the need to handle well at low-speeds; it performed better than many of the opposing naval aircraft it was sent-up against.
  • The plane was stressed for extremely high g-loads (13.5 ultimate) and had maneuvering flaps that allowed a wide range of extension to help tighten the turning arc (it could stay with a A6M all the way down to 205 mph, instead of around 240-300 like the F4F owing to this)
  • Turning arc was probably pretty good against land-based aircraft -- seemingly similar to the Spitfire and Hurricane
 
I thought docile handling was the ease at which a plane could be flown especially in adverse conditions.
That's a pretty good description.
With regard to a carrier borne aircraft it may or may not be in combat with the enemy, it always has to be landed back on the carrier. Over the course of naval combat with carriers I believe more planes have been destroyed by the ship that carried them than the enemy in carrier operations
Or the ocean...

In general three things aren't readily found in performance statistics:
  • Control harmonization. An aircraft with disparate forces required for pitch, yaw, and roll will be less pleasant and more tiring to fly
  • Departure characteristics. An aircraft that gives a predictable warning near stall and can be recovered quickly will be easier to fly in combat.
  • Dynamic behavior, that is how quickly the aircraft accelerates in roll (especially), pitch, and yaw
I know I might get into splitting hairs, but to be clear -- with dynamic behavior -- you mean how quickly it takes for a plane to build up a pitch-rate/g-load; a roll-rate, and yaw-rate?

Along the same lines, ideally, one would want a very high peak Coefficient of Lift for lower stall speeds, and very little migration of the center of lift so that the aeroplane behaves in a predictable fashion.
Some aircraft have more of a shift in the center of pressure during stalls?
I believe also that "control modulation" or the relationship of aircraft response to control inputs is a factor that is very important but also not often mentioned. Certain aircraft can be held at a certain G-Load without difficulty while others are much less precise and will constantly overshoot or undershoot the target.

Along with control forces, there is also the relationship of the movement of the stick to the response of the aircraft.
These two kind of go hand in hand and has to do with both predictable inputs to maneuvers, and muscle memory...
Control coupling also tends to result in less than predictable behaviour but only tends to get mentioned with more modern high performance aircraft.
From what I remember there was roll/yaw coupling and that occurred at higher AoA with aircraft that had short wings, a long fuselage, and a lot of mass in the middle right?

"predictable behaviour" must surely count as an intangible when you're fatigued and or wounded.
Agreed

Handling around stall (F6F and Bf 109 excelled at this, ailerons remained effective through the stall)
Good point, and I'd also put the ability to recover quickly from a stall...
Sensitivity in trim to speed changes (most WWII fighters were VERY speed sensitive, not the Fw 190)
I'm confused -- thought that was a good trait in the Fw-190?
5) Ergonomics of cockpit (how easy is it to get to and use the various gauges and switches)
The P-51 was very good in that regard -- the cockpit was laid out in an intuitive manner that was easy to use. The F-15 was also well regarded in this role (though one that flew a great deal later), the F-105 had some areas that left a lot to be desired (though also a design well after WWII, though before the F-15), when it came to switching the gunsight from air-to-ground to air-to-air.
Ease of handling the powerplant (easy to set for good power without much thought or time)
Yeah the LaGG-5 had a whole bunch of levers that were needed to fine tune the engine. The Fw-190 used some kind of electro-mechanical computer. On a more simple level, some aircraft had automatic boost control, and others didn't.
Gunsight (+ or -)
Actually there were many types of gunsights. The ring-n-bead, the reflector, and there was the lead-computing optical sight. I'm not sure if any fighters had (early on) a gunsight that was like a scope...
Convergent or nonconvergent armament (guns in nose or wings)
That gave the P-38 a great advantage at range.
Cockpit comfort (heater at high altitudes, fresh air inlets, seat ergonomics)
Fresh-air inlets avoid recycling the air, right? I'd also think variables such as raising the pilots feet to increase g-tolerance as a useful trait.
11) Landing gear issues (tippy or rolley on ground … see Bf 109: very rolley, will NOT nose over, and Spitfire, not very rolley, but noses over easily ... Griffon unit)
Wheelbarrowing...
Ram air or not (Hellcat did not have it, Corsair did. MANY Corsairs went in around carrier from carb ice in cooler weather, no Hellcats did)
It can be an advantage and disadvantage. No ram-air reduces the odds of ice-forming in the intake, but high ram-compression also provides you with a greatly increased aircraft critical altitude.
Reliable powerplant or not
I'd have placed that up with the ease of handling the powerplant.

CORSNING said:
dive speed. That one is going
to be a rough one because maximum allowable indicated
changed with altitude.
At higher altitudes the limit is often that of mach number and compressibility effects; at lower altitudes the airspeed limit becomes more serious of a matter. I would also consider dive-acceleration to be a trait that could be good or bad.

Good: I can dive away from somebody real fast, even if he has the same maximum airspeed and maximum mach number as me; like wise if the situation is reversed, I can run him down effectively.

Bad: If I have a lower mach limit, and I accelerate really fast, I can quickly end up in mach-tuck territory, and find myself unable to get out of a dive.
Combat Speed is a range of maximum possible speeds that an aircraft can develop for the conduct of active maneuver aerial battle, and at which all forms of maneuver attendant to that battle can be executed.
Is this connected to corner-velocity?
 
The plane was stressed for extremely high g-loads (13.5 ultimate) and had maneuvering flaps that allowed a wide range of extension to help tighten the turning arc (it could stay with a A6M all the way down to 205 mph, instead of around 240-300 like the F4F owing to this)

Great stuff Zipper but I have to tweak your comments a bit regarding the Hellcat's Max G-loading and flap usage. According to the pilot's manual the F6F's airframe is rated for +7.0G/-3.0G below 320 knots IAS and +5.5G/-2.5G above this airspeed. I have read action reports where pilots have stressed the Hellcat to above +8G but this was considered an "Over G" condition and the airplane needed to be inspected after it returned from it's mission if this occurred. And then there were various G load ratings at different altitudes between these limits while performing diving maneuvers.

For "unlimited use of ailerons" and use of "Maneuver Flaps" the aircraft was rated for +5.0G/2.0G. Now, the flaps on the Hellcat were either up or down so there was no intermediate settings like with the Corsair. This is not to say that Hellcat pilots didn't deploy these flaps in such a fashion but drag increased so much that this tactic was prohibitive if it bled off too much airspeed after the turn and ended up leaving the pilot at a tactical disadvantage.
 
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According to the pilot's manual the F6F's airframe is rated for +7.0G/-3.0G below 320 knots IAS
Grumman set out to build a "baby buggy" easy to fly, hard to break fighter, and possibly they rated it for a greater safety margin than the customary "limit x 1.5 = ultimate"? Perhaps as a concession to the inevitable combat weight "inflation" that seems to beset all military aircraft. Between limit G and destruction G there's an intermediate value which is deflection or deformation G beyond which a structure bent or deflected under load doesn't return to its original form when load is removed. (Think "bent" Sabres returning from Migfights in Korea.) Do you suppose Grumman selected this value to apply their 2/3 safety margin to?

Now, the flaps on the Hellcat were either up or down so there was no intermediate settings like with the Corsair.
Which model Hellcat are you talking about here? I remember reading in my younger days of the Hellcat having a "Combat" position for its flaps between "Up" and "Landing". Perhaps on the second (-5?) model?
Cheers,
Wes
 
Do you suppose Grumman selected this value to apply their 2/3 safety margin to?

Sounds about right. The F4U-1 was rated for a max G of +7.5/-5.5 and I think both aircraft could be safely flown to greater limits than those posted in flight manuals. Without knowing the structural differences (if there were that many) between the F4U-1 and -4 I really can't determine why the latter version was rated up to +9G/-4G. We'll need someone with greater knowledge of the Vought bird to clarify this for us.

Which model Hellcat are you talking about here? I remember reading in my younger days of the Hellcat having a "Combat" position for its flaps between "Up" and "Landing". Perhaps on the second (-5?) model?
Cheers,
Wes

Both the -3 and -5 had similar flaps, very simple to use with an "Flaps Up/Flaps Down" switch next to the power plant controls and there was also a hand pump that the pilot could use to raise/lower them in an emergency situation as well, such as with an hydraulic pump failure. Now maybe the pilot could partially extend/retract the flaps with this procedure (35 double strokes were required for extension and 25 for retraction) but it obviously wasn't something a pilot would use in a normal flight situation and certainly not in the heat of combat if the system was operating properly.

Maybe you are confusing it with the Corsair????
 
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DarrenW said:
Great stuff Zipper but I have to tweak your comments a bit regarding the Hellcat's Max G-loading and flap usage. According to the pilot's manual the F6F's airframe is rated for +7.0G/-3.0G below 320 knots IAS and +5.5G/-2.5G above this airspeed.
+10.5g/-4.5g ultimate below 320; +8.25g/-3.75g above 320
For "unlimited use of ailerons" and use of "Maneuver Flaps" the aircraft was rated for +5.0G/2.0G.
+7.5/-3 ultimate, which is might actually be quite good..
Now, the flaps on the Hellcat were either up or down so there was no intermediate settings like with the Corsair.
Oh, I thought they both had it?

Grumman set out to build a "baby buggy" easy to fly, hard to break fighter, and possibly they rated it for a greater safety margin than the customary "limit x 1.5 = ultimate"?
Possible...
I remember reading in my younger days of the Hellcat having a "Combat" position for its flaps between "Up" and "Landing". Perhaps on the second (-5?) model?
I thought they had a maneuvering setting too...
 
Both the -3 and -5 had similar flaps, very simple to use with an "Flaps Up/Flaps Down" switch next to the power plant controls and there was also a hand pump that the pilot could use to raise/lower them in an emergency situation as well, such as with an hydraulic pump failure. Now maybe the pilot could partially extend/retract the flaps with this procedure (35 double strokes were required for extension and 25 for retraction) but it obviously wasn't something a pilot would use in a normal flight situation and certainly not in the heat of combat if the system was operating properly.

Maybe you are confusing it with the Corsair????

Hello DarrenW,
If I remember correctly, the Flaps on the Hellcats would only extend as far as the aerodynamic loads permitted.
Thus if the pilot were to select "Flaps Down", if the airspeed were high enough, the flaps would not deploy completely and perhaps that might still be useful in combat.

- Ivan.
 
In no way could the F6F stay with an A6M. In another thread we were treated to three Air Combat documents from the war. One specifically addressed the Hellcat versus the A6M and it was plainly stated that the F6F would never dogfight with an A6M and in no way matched maneuverability with one.

What it COULD do was out-climb and out-accelerate the A6M, and was also faster. Add to that the ability to stay with the A6M for long enough (90° or less) to get in a deflection shot and then climb away, and the ability to take punishment that would blow an A6M apart, and you have a winner IF the pilot accepts the correct methods of air combat with the more maneuverable but more delicate foe. Most did, as the "Ace maker" made plain by war's end. The "Ensign Eliminator," (F4U) did well, too, but the F6F decided the contest outcome in the Pacific, at least coupled with a lucky Naval engagement or two.

They COULD have done without the Corsair, but the converse is not true. In the end, the Corsair was a great fighter, too, possibly better than the Hellcat. But not so in the beginning. It almost got cancelled, and the Hellcat would have won anyway had that happened. We MIGHT have had the F6F-6 and follow-ons but they decided to develop the F8F instead. So, it was limited to two prototypes. We KNOW they would have fitted a more powerful engine because they did in production aircraft. I suspect they would also have fixed the roll rate and made more improvements, but the war was winding down anyway by then.
 
Thus if the pilot were to select "Flaps Down", if the airspeed were high enough, the flaps would not deploy completely and perhaps that might still be useful in combat.
VERY interesting. Thinking from a mechanic's perspective, did it have some sort of an "overload shutoff" that would turn off the actuating system when flap extension stalled due to aerodynamic overload? That would make sense to save wear and tear on a critical system that's already subject to hard usage.
Now from the pilot think perspective, this would be the best of both worlds; an infinitely variable "combat flap" that would give you the best boost to your turning ability possible at the ambient speed and G load. As you approach firing range, start rolling left, keeping your gunsight on target with rudder (you know Saburo is not going to roll right, and when he goes left, he'll out-roll you), then when he goes, bang down the flap switch and honk on the Gs. After 90° of turn, if you haven't got a shot and aren't gaining any lead (or if he fooled you and rolled right), it's flaps up and reach for the sky, keeping an eye out for a possible re-attack on him from overhead. Don't forget to check six for his top cover, who are likely trying to close out your account!
Cheers,
Wes
 
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...
The "Ensign Eliminator," (F4U) did well, too, but the F6F decided the contest outcome in the Pacific, at least coupled with a lucky Naval engagement or two.

They COULD have done without the Corsair, but the converse is not true. In the end, the Corsair was a great fighter, too, possibly better than the Hellcat. But not so in the beginning. It almost got cancelled, and the Hellcat would have won anyway had that happened. We MIGHT have had the F6F-6 and follow-ons but they decided to develop the F8F instead. So, it was limited to two prototypes. We KNOW they would have fitted a more powerful engine because they did in production aircraft. I suspect they would also have fixed the roll rate and made more improvements, but the war was winding down anyway by then.

I'm afraid that several claims don't match well with history. For example, F6F didn't decided outcome in Pacific, that was decided far earlier than F6F ever fired it's guns in anger.
Corsair was never in danger of being cancelled. Neither F6F nor F4U were in the ww2 beginning, not even of beginning of Pacific war.
 
Well, Tomo, we'll just have to disagree. But, that's OK, no worries.

I think the Hellcat DID make the difference. The histories I have read were pretty clear that the Corsair was in real danger of never being deployed on a US carrier, and there were voices who wanted it gone. If fell to the British to embarrass the USN and deploy them on carriers first. After that, it was hard to argue they weren't suitable for carrier deployment. My post above in no way diminishes my liking for the F4U. I think of it as one of the best of the radial fighters. But, it wasn't at the start of its career, and the Hellcat was always a winner, at least after it was fitted with the R-2800, which was VERY early. Second airplane, if I recall.
 

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