Most Overrated aircraft of WWII.....?

[Zipper730]

Supersonic? Really?

It sounded ridiculous to me too!

 

[wuzak]

W-w-w-wait... The drawings were reworked simply to mirror and flip them? I thought there was a problem with the British and US inch being like a tiny fraction of an inch off and that's why there were problems with British aircraft using American V-1650's?

There was no mirroring. The views were rearranged.

In first angle the left view was on the left and the right view was on the right.

They also had to fit US sourced equipment, such as the carburetor, and come up with a way for joining the cooling passages between the head and block (which was later changed to the Rolls-Royce design), because Rolls-Royce changed the design to a two piece design (separate head) but had yet to implement it in British production..

In third angle the views were on opposite sides.

Packard Merlins were predominately used in British aircraft, particularly the single stage engines.

 

[Zipper730]

There was no mirroring.

I've never been spectacular with visual puzzles, but it looked like it was sort of flipped/mirrored. I stand corrected.

They also had to fit US sourced equipment, such as the carburetor, and come up with a way for joining the cooling passages between the head and block (which was later changed to the Rolls-Royce design), because Rolls-Royce changed the design to a two piece design (separate head) but had yet to implement it in British production.

So, we were a little bit ahead in that one case.

Packard Merlins were predominately used in British aircraft, particularly the single stage engines.

I just remembered that certain British aircraft had special variants for the Packard Merlin (i.e. Lancaster Mk.III, and Spitfire Mk.XIV).

 

[wuzak]

So, we were a little bit ahead in that one case.

If you count having the designs and sample engines sent to you then, yes, you were ahead.

I just remembered that certain British aircraft had special variants for the Packard Merlin (i.e. Lancaster Mk.III, and Spitfire Mk.XIV).

The Spitfire Mk XIV had a rolls-Royce engine. The Griffon 65, or similar.

I think you mean the XVI.

There was small differences that required changes, notably the injection carburetor on the Packard Merlin 28 requiring different controls for the Lancaster III. Or the slight airframe changes required due to the slightly different height of a Merlin 266 vs a Merlin 66, due to the intercooler, as we were informed recently in this forum.

 

[Zipper730]

The Spitfire Mk XIV had a rolls-Royce engine. The Griffon 65, or similar. . . . I think you mean the XVI.

I'm not good with Roman Numerals...

 

[pbehn]

That theoretical speed was like 800 TAS right?

Yeah, you'd need an entire reworking of the internal structure.

I now have no idea what you are discussing, aileron reversal, transonic aerodynamics or the speed of a drawing?

 

[Peter Gunn]

I now have no idea what you are discussing, aileron reversal, transonic aerodynamics or the speed of a drawing?

Ah, Pepsi through the nose, no feeling like it.

 

[pbehn]

Ah, Pepsi through the nose, no feeling like it.

I have been asked to estimate the dive performance of a sketch in the past.

 

[Zipper730]

I now have no idea what you are discussing, aileron reversal, transonic aerodynamics or the speed of a drawing?

Okay, let's start this from the top.

1. I remember it being said that the Spitfire Mk.VII/VIII/IX had strengthened spars that were good to 800 mph: I assumed it implied the wings as a whole could reach that speed (assuming the fuselage it was attached to could).
   • This was first told to me from a person I know online
   • It then came up again on this forum some time back.
   • Then it came up on this post, but talked about the Mk.21 wing, and regarded aileron reversal only
2. A person I talked to online sort of came up with a "What-If" gag-design regarding a fighter called the Jetfire that would...
   • Use Spitfire Mk.21 wings as a baseline.
   • All moving tailplane
   • F.2/4 Beryl engine
3. Drawings usually don't have speeds with the exception of
   • You factor in the velocity of the Earth around the Sun, the Sun around the Galaxy, etc
   • The drawing is on something that's moving (such as an aircraft)
   • A guesstimate as to the speed of an aircraft, spacecraft, both, on a drawing

Okay, so we both up to speed?

 

[pbehn]

Okay, let's start this from the top.

1. I remember it being said that the Spitfire Mk.VII/VIII/IX had strengthened spars that were good to 800 mph: I assumed it implied the wings as a whole could reach that speed (assuming the fuselage it was attached to could).
   • This was first told to me from a person I know online
   • It then came up again on this forum some time back.
   • Then it came up on this post, but talked about the Mk.21 wing, and regarded aileron reversal only
2. A person I talked to online sort of came up with a "What-If" gag-design regarding a fighter called the Jetfire that would...
   • Use Spitfire Mk.21 wings as a baseline.
   • All moving tailplane
   • F.2/4 Beryl engine
3. Drawings usually don't have speeds with the exception of
   • You factor in the velocity of the Earth around the Sun, the Sun around the Galaxy, etc
   • The drawing is on something that's moving (such as an aircraft)
   • A guesstimate as to the speed of an aircraft, spacecraft, both, on a drawing

Okay, so we both up to speed?

What does "good for" mean? Just because a calculation says you have aileron reversal at 850MPH doesn't mean anything other than that. Between the speed where trying to roll left rolls left and trying to roll left actually rolls right you have a range of speed where it doesn't roll at all, that is why you want the reversal speed well in excess of any actual speed you want to go.

 

[Zipper730]

What does "good for" mean?

If a person generally was to say: "The plane's good to 800 mph" it means it would be able to either fly at that speed, fly at that speed if enough power was present, or the component would hold together at that speed.

Just because a calculation says you have aileron reversal at 850MPH doesn't mean anything other than that.

So it was more a hypothetical figure based only on force and torsional loads on the wing.

 

[Zipper730]

Ah, Pepsi through the nose, no feeling like it.

Actually I've had coke, pepsi, and probably sprite up the nose, they all feel about equally unpleasant.

 

[pbehn]

If a person generally was to say: "The plane's good to 800 mph" it means it would be able to either fly at that speed, fly at that speed if enough power was present, or the component would hold together at that speed.
So it was more a hypothetical figure based only on force and torsional loads on the wing.

The discussion is based on what you assumed from what you thought you read implied.

 

[pbehn]

Okay, let's start this from the top.

1. I remember it being said that the Spitfire Mk.VII/VIII/IX had strengthened spars that were good to 800 mph: I assumed it implied the wings as a whole could reach that speed (assuming the fuselage it was attached to could).
   • This was first told to me from a person I know online
   • It then came up again on this forum some time back.
   • Then it came up on this post, but talked about the Mk.21 wing, and regarded aileron reversal only
2. A person I talked to online sort of came up with a "What-If" gag-design regarding a fighter called the Jetfire that would...
   • Use Spitfire Mk.21 wings as a baseline.
   • All moving tailplane
   • F.2/4 Beryl engine
3. Drawings usually don't have speeds with the exception of
   • You factor in the velocity of the Earth around the Sun, the Sun around the Galaxy, etc
   • The drawing is on something that's moving (such as an aircraft)
   • A guesstimate as to the speed of an aircraft, spacecraft, both, on a drawing

Okay, so we both up to speed?

I wouldn't say wiki is a cast iro source but the attached discusses the development of the Spitfire wing to the Supermarine Spiteful. Seafang and Attacker. None of these were 800MPH aircraft and neither was the next generation like the Hawker Hunter.
Supermarine Spiteful - Wikipedia
Supermarine Seafang - Wikipedia
Supermarine Attacker - Wikipedia

 

[Zipper730]

Look, I'm not saying that the Spitfire could do 800 miles an hour. Nobody is saying that. I remember it being said that the spars of the wing were good enough for it, though that would be based on the presupposition that...

1. The airplane had no propeller
2. The fuselage was different
3. The tailplane was different, and likely all moving

In other words, the plane would be different except for the wings, if those figures were even right. If it's just based on torsional load tolerance, then it's possible that the wings would have produced enough turbulent flow over them that it would've interfered with the airflow over the tail producing a tuck-under well before then. Even if not, the ailerons would have probably fluttered and broke up before then, and you would have entirely new problems on your hands.

 

[pbehn]

Look, I'm not saying that the Spitfire could do 800 miles an hour. Nobody is saying that. I remember it being said that the spars of the wing were good enough for it, though that would be based on the presupposition that...

1. The airplane had no propeller
2. The fuselage was different
3. The tailplane was different, and likely all moving

In other words, the plane would be different except for the wings, if those figures were even right. If it's just based on torsional load tolerance, then it's possible that the wings would have produced enough turbulent flow over them that it would've interfered with the airflow over the tail producing a tuck-under well before then. Even if not, the ailerons would have probably fluttered and broke up before then, and you would have entirely new problems on your hands.

So you didn't read the link then?

 

[XBe02Drvr]

So you didn't read the link then?

Does he ever?

 

[Zipper730]

So you didn't read the link then?

Actually, I read these articles before, so I didn't see a need. That said, I decided to re-read them. Interestingly, since no data was listed for change in mach limits, I did a search for it. Ironically, when I did, I stumbled upon this post.

In this post the following was stated by you, tomo pauk, and Koopernic

You

Don't get hung up on the high mach number of the Spitfire, at those speeds the plane is at the edge of control and the propeller likely to fall off, it was drag at lower speeds that was important.

tomo pauk

Designers expected that drag would've been lowered, and the critical Mach number would've been increased by 55 mph.

Koopernick

The theoretical speed at which the wing would reverse was theoretical only and didn't happen in real life. It reduced aileron effectiveness to about 65% at 400 mph. The torsional stiffness of the wings on the mark 21, 22 & 24 was increased by 47% over previous marks, raising the theoretical aileron reversal limit from 580 to 825 mph IAS. These marks really were post war aircraft though a few did see service in 1945 but not air to air combat. The Mk XVIII didn't get a new wing but it used better materials such as a stainless steel main spar.

Well, all that said: It appears the 825 mph figure seems based only on airspeed (it's not clear mach number is factored in at all), and regards aileron reversal only; they expected an increase in critical mach number of about 55 mph (unsure what the Spitfire's critical mach number is -- you don't see problems with performance until you're at the drag divergence point), unless they meant placard limit (in which, they appeared to have miscalculated).

I think we can solidly agree, this subject has been beaten to death, and actually resolved.

BTW: Considering the older post, I guess I wasn't experiencing deja-vu after all. That only occurs when you think you've done something before, and you haven't.

 

[pbehn]

Actually, I read these articles before, so I didn't see a need. That said, I decided to re-read them. Interestingly, since no data was listed for change in mach limits, I did a search for it. Ironically, when I did, I stumbled upon this post.

In this post the following was stated by you, tomo pauk, and Koopernic

You


tomo pauk


Koopernick
Well, all that said: It appears the 825 mph figure seems based only on airspeed (it's not clear mach number is factored in at all), and regards aileron reversal only; they expected an increase in critical mach number of about 55 mph (unsure what the Spitfire's critical mach number is -- you don't see problems with performance until you're at the drag divergence point), unless they meant placard limit (in which, they appeared to have miscalculated).

I think we can solidly agree, this subject has been beaten to death, and actually resolved.

BTW: Considering the older post, I guess I wasn't experiencing deja-vu after all. That only occurs when you think you've done something before, and you haven't.

Try reading the links again.

 

[thom regit]

Ah, Pepsi through the nose, no feeling like it.

Black coffee through the nose has a real kick and adds a sour bouquet with prolonged, bitter aftertaste.
It's an acquired taste....recommended for experienced snorters only.