F4U vs F6F & Top-Speed: Let's Settle This

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i always thought that the static ports were on the pitot tube
Not always: If you have the static ports on the pitot tube, it's called a pitot-static tube. If you have the static ports elsewhere, it's called a pitot-static system. Technically it's a pitot static system regardless.

I guess you could say that all pitot-static tubes are pitot-static systems, but not all pitot-static systems are pitot-static tubes.
 
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Then how did you know how fast you were going at?
Have you ever heard the word "interpolate"? This is one of the many things in flying where you have to depend on experience and a "feel for what's happening" rather than going blindly "by the numbers". Even a Boeing, despite its far more sophisticated static system, will experience an IAS error in a sideslip condition. (Something they don't do much!) In a Cessna 150 (or, I suppose an F6F-5), you note the airspeed before starting your slip, then note again after the slip is established, to give you a correction factor + or - . Hold your airspeed at the corrected value.
In practice, following this exactly has your eyes inside the cockpit too much, so you must quickly learn how pitch attitudes and slip angles can control your airspeed in a slip by visual reference "eyes out". This is where the "truck drivers", "bulldozer operators" and "armchair aces" weed themselves out of the program and the motorcyclists, equestrians, sailors, and gymnasts excel.
the way one would carry out an approach almost certainly revolved around simply focusing on alpha and glide-path to determine this.
The very essence of all phases of flight. This is why the Squids and the Jarheads have been ahead of the rest of aviation for decades! IT'S ALL ABOUT AOA!! Airspeed/weight/configuration tables are all crutches to hobble you down the path to the holy grail, which is Angle Of Attack, the ultimate determinant of airframe performance and behavior. Terrestrial aviation seems to have a problem absorbing this fact, as so many planes have the sensors, which feed various systems, but don't display AOA to the crew.
Cheers,
Wes
 
So, I guess you just have to develop a feel for it in practice. The hardest part to grasp that I would see, is gauging changes in speed (if the speed is reading nothing) either eyes in or outside the cockpit.
This is where the "truck drivers", "bulldozer operators" and "armchair aces" weed themselves out of the program and the motorcyclists, equestrians, sailors, and gymnasts excel.
Actually, that's the funny thing about the DMV. It teaches you to drive eyes on the gauge. One MPH over during the road test, and you lose. Now, in real life -- you don't constantly monitor the gauge: You just focus on the other cars. If you're passing everybody really fast, then you're going too fast; if everybody is passing you, and you're getting honked at: You're probably going too slow.
This is why the Squids and the Jarheads have been ahead of the rest of aviation for decades! IT'S ALL ABOUT AOA!!
And for descent, you also use the ball to determine glide-path.
Airspeed/weight/configuration tables are all crutches to hobble you down the path to the holy grail, which is Angle Of Attack, the ultimate determinant of airframe performance and behavior.
The problem is at high speed, you have to remember what AoA limits correlate to the limiting/ultimate g-load. I figure muscle memory helps out for that.
Terrestrial aviation seems to have a problem absorbing this fact, as so many planes have the sensors, which feed various systems, but don't display AOA to the crew.
I remember Chuck Yeager didn't have that particular problem. In fact, he criticized the F-15's AoA gauge, saying if you don't know what that that is, you shouldn't be flying.

Thanks Tomo, it's quite tasty!
I think the most common agreement on this forum is bacon tastes good. Honestly, there are wildly varying views on so many things, but we all agree on bacon. Sad for the pigs, but ironically, pigs like the taste of bacon too...
 
The hardest part to grasp that I would see, is gauging changes in speed (if the speed is reading nothing) either eyes in or outside the cockpit.
First of all, you will never see "nothing" on the ASI unless you're fully stalled and tumbling ass over teakettle, and then not for very long. Second, you have many clues to airspeed besides the gauge, such as sound, attitude, vibration, stall horn, and experience. If you're the "white knuckle" type, anxiety will probably prevent experience from coming into play.

The problem is at high speed, you have to remember what AoA limits correlate to the limiting/ultimate g-load.
Listen, if you're in a machine built for turn 'n burn and you're anywhere near ultimate G load, you're going to be struggling to maintain consciousness and too greyed out to read the G meter precisely, much less calculate AOA equivalents. And if in a plane NOT designed for such antics, what are you doing there in the first place??

I remember Chuck Yeager didn't have that particular problem.
He was the real deal. The ultimate class act. On a par with John Glenn.
Cheers,
Wes
 
First of all, you will never see "nothing" on the ASI unless you're fully stalled and tumbling ass over teakettle, and then not for very long.
You said the speed gauge would go to zero in large slips...
Second, you have many clues to airspeed besides the gauge, such as sound, attitude, vibration, stall horn, and experience.
So there are additional cues to use? While not related to flying, it relates to driving: While the blind spot will not allow you to see a car in the mirrors, you actually can often tell they are present. The whoosh sound of the car displacing is audible and right about the time it slips into the blind spot, you can hear it (my vision sucks, but my hearing is pretty good for a guy in his mid 30's).
If you're the "white knuckle" type, anxiety will probably prevent experience from coming into play.
Generally I've been heavily knowledge driven, and some are able to desensitize one's self.
Listen, if you're in a machine built for turn 'n burn and you're anywhere near ultimate G load, you're going to be struggling to maintain consciousness and too greyed out to read the G meter precisely, much less calculate AOA equivalents.
So as long as the controls aren't too light, you should be okay if you have good muscle memory, in that particular case?
He was the real deal. The ultimate class act. On a par with John Glenn.
Both were awesome in their own right.
 
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If you're in BOS, NYC, Philly, DC, etc, and you're less than 15 over the limit, you're an obstacle to traffic and a road hazard. You can have it. I'll settle for Podunk, USA.
Oh, in that case, just drive at the same speed as everybody else. If they're going faster, you're not doing it right, and if they're going slower, you might want to consider your driving habits
 
You can desensitize people with anxiety.
Tell me about it. As a flight instructor, that's what I did for a living. It works for most folks eventually, but the hard core white knucklers never seem to come around, and if they have any sense, self-select out of flying.

ould be okay if you have good muscle memory, in that particular case?
That's what stick force gradient is all about. If it takes a lot of effort to maintain a high G load, then a pilot blacking out will relax back stick pressure, relieving the G load. FBW planes, with their lack of control feel, don't have this protection, unless artificially built in.
Oh, in that case, just drive at the same speed as everybody else. If they're going faster, you're not doing it right, and if they're going slower, you might want to consider your driving habits
75 MPH bumper to bumper on the beltway or 50 MPH on city streets doesn't leave enough reflex time.
No thank you!
Cheers,
Wes
 
You said the speed gauge would go to zero in large slip
I suggest you RE-READ this entire thread and pay attention to who said what. The ASI at zero in a slip was a reference to the F6F-5 after the pitot static system had been modified. I personally suspect the accuracy of that statement is questionable. Otherwise, it points to an egregiously bad design.
What I said was that a C150 in level cruise flight could drive its ASI anywhere from Vstall to Vne just by stomping on the rudder and generating a sideslip.
Maybe you should take notes as you read, as you seem to have a penchant for misquoting folks and getting your facts back-to-front in your posts.
'Nuf said,
Wes
 
Corky Meyer's statement that the Hellcat's speed was systematically high (10 knots? I can't remember) must be taken with a grain of salt. Let's look at the Hellcat's role as a long-distance carrier fighter. Pilots had to be able to fly on instruments over water for about 400 miles each way then find a carrier that was moving the whole time. If the the F6F's airspeed indicator was 10 knots off, that would have been discovered the first time a fighter wasn't where he expected to be.
 
I suggest you RE-READ . . . . What I said was that a C150 in level cruise flight could drive its ASI anywhere from Vstall to Vne just by stomping on the rudder and generating a sideslip.
Yeah, I did misread that. I stand corrected.
 
If the the F6F's airspeed indicator was 10 knots off, that would have been discovered the first time a fighter wasn't where he expected to be.
I think you're crediting long range overwater dead reckoning navigation with a bit more precision than existed at the time. Winds aloft data was nowhere near as detailed and complete as it is today, with every airliner's GPS and ACARS updating constantly in real time. 400 miles each way provides plenty of opportunity for variations in wind aloft to obscure a 10 knot error in airspeed.
Cheers,
Wes
 

Ok, but given that, flying many flights of different types of aircraft, if the F6F was always off more than the others, it would begin to show.
 

In his book Meyer says, "A dual orfice system located way behind the lowered flaps, similar to the Corsairs, finally provided a satisfactory means to give the Hellcat a cockpit indicated airspeed reading comparable to the vaunted Corsair. That was the last we heard of the Hellcat's performance gap with the Corsair."

Again I wonder if the Navy fliers were so ignorant they didn't know to apply the installation error corrections when comparing Hellcat to Corsair.

That performance report says the Hellcat engine was down on power, perhaps due to the carburetor not metering correctly. Heavy carbon deposits on the side of the plane are mentioned. It's not the first time I've see a complaint of substandard engine performance in those reports. Maybe that was the reason Grumman's tests showed Hellcat and Corsair evenly matched in speed. If the engine of their one Corsair exemplar was a little below par, that could account for the result.
 
Again I wonder if the Navy fliers were so ignorant they didn't know to apply the installation error corrections when comparing Hellcat to Corsair.
That depends on the accuracy of the error corrections. There's nothing cut and dried about these things. They're arrived at by theoretical calculatiions modified by measurements and testing and more measurements and more testing, and then the discovery that repeated identical tests are creating inconsistent results, and it's back to the drawing board. And test pilots are well aware of all the details and how to do the calculations, many of them being engineers by training, and practically all graduates of test pilot schools.
Pitot tubes are relatively cut and dried; as long as they're in undisturbed air, their errors are going to be more or less proportional to their misalignment with the relative wind, and that will be determined by AOA and slip angle, if any. Static ports, OTOH, are a much more challenging proposition. An airplane is a complex curvy shape awash in a tornado of its own making, and finding locations where an accurate sample of static atmospheric pressure can be sensed at all possible AOAs and slip angles is nigh impossible. So we settle for what we can get, and live with the resulting errors, bearing in mind that the correction factors are themselves far from perfect. Not a comfortable place for those addicted to cast iron certainties anchored in concrete.
Cheers,
Wes
 

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