Stability and Control characteristics of the Early Mark Spitfires

[CaptainDoggles]

Originally Posted by 41Sqn_Banks

Mass doesn't matter in vertical acceleration*

That's only true in a vacuum. You have to account for density (among other things) when in the atmosphere.

[robtek]

Originally Posted by 41Sqn_Banks

Again I don't get the discussion. All source state that spin recovery is pretty standard for Spitfire. The only "problem" is the light elevator/relative instability, which makes precise control more difficult than in other aircraft, but this is only a issue if the pilot is not used to the aircraft.
It's like driving a car with a sensitive clutch. You must be careful on the first day, but after a week it won't make a difference and you make use of the benefits.

The thing is that if a pilot has a stall a bit closer to the ground and has to recover under stress, as the ground is rising to meet him, it takes nerves of steel to first let the speed build up to 150 mph in a vertical dive and then to gradually recover from the dive.

In the Spitfire it should be possible to overstress the plane if not done correctly as there is only about 2lbs per g stick force needed, where in other planes the pilot may not have the power to recover soon enough or to overstress the airframe.

[Glider]

Originally Posted by Crumpp

You mean like the fact it is not the specified fuel in the portion of the Operating Notes entitled "Notes on a Merlin Engine" is a strong indicator the fuel is still undergoing service testing?

I never disputed the fuels use, just the silly notion it was the only fuel available and the adopted service fuel.

Who would ever suggest they were still undergoing 100 Octane fuel testing in August of 1940 simply on the basis the facts do not align?



100 Octane is completely off topic. Start your own thread if you want to debate it.

These tests were on the 100 octane fuel produced in the UK as a back up in case the supplies from the USA were insufficient

[Glider]

Originally Posted by robtek

There might be hundreds of Spitfires being lost over sea or behind enemy lines because of mishandling in stress situations, all disregarded because being accorded to enemy action.
Nobody knows that for sure.
The only data we have is a per se incomplete list of researched accidents.

As probably 90% of Mk I and Mk II combats were over the UK I doubt that hundreds were lost behind enemy lines or over the sea. So the comment about a lack of examples is a valid one.

One has been identified in volved in a spin. Crumpps comment was typical The never changed it because a high speed dive is generally the result of spin recovery and a Spitfire pilot could break the airplane rather easilyThe fact that this example was in a high speed dive from low cloud, then did a violent pull up presumably to avoid hitting the ground, suffered a high speed stall, then spun and then had a wing failure tells me that it was far from easy to break a Spitfire wing. It was very difficult.

Edit - I should add that to say that a high speed dive is generally the result of a spin recovery is rubbish, any pilot with spin experience would know that. In combat a high speed dive is normally the result of combat, trying to evade or bounce an enemy aircraft. Spinning is slow speed activity and recovering doesn't take long you have to wait until you have sufficient speed. Its the wait that is often the more dangerous time as if you try to pull out with insufficient speed the plane tends to sink (often called mush)and can still hit the ground. Holding your nerve until speed has been reached with the ground coming up can be difficult for some pilots to learn.
If you are in a high speed spin you are normally dead whatever happens to the plane as you will be trapped by the G forces, unable to open the cockpit or get out

[Crumpp]

150 mph, in a vertikal dive, with a GRADUALLY recovery, surely you'll reach a pretty high velocity before leveling out, accelerating all the time.

Exactly.

Your thrust vector adds to gravity, lift opposes drag <unless you dive a zero lift angle>

In short, away you go...

in an aerobatic plane.

Like the one in my hanger???

That passenger is Col. Phil Lacey.

The Fitzpatrick Custom was just a dream in 1947 when a former World War II fighter pilot, Phil Lacey, showed his friend Al Fitzpatrick some of his car sketches.

Read more: http://www.autoweek.com/article/2006...#ixzz22txOQq1j

Col. Lacey flew P-40's, P-39's, and P51's with the 8th USAAF in World War II. In Korea he flew F-86's and Vietnam, Canberra bombers.

You don't what aerobatics is until you seen Phil take the stick, LOL. That old man can fly the paint off an airplane.

And yes, he reads and abides by the Operating Notes.....

[Crumpp]

I should add that to say that a high speed dive is generally the result of a spin recovery is rubbish

Read the Operating Notes.....

150 mph, in a vertikal dive

BTW, you are not necessarily going to be vertical nor is certain you will enter a high speed dive.

There is a good possibility of that happening.

[Sandstone]

Wow, Lacey must be one of the oldest aerobatic pilots flying. At least 92, I'd guess, if he flew in WWII. Good for him!

[bongodriver]

Exactly.

Your thrust vector adds to gravity, lift opposes drag <unless you dive a zero lift angle>

In short, away you go...

Negative....if you are throttle closed then there is no thrust vector to add and a disking prop adds to drag, acceleration is 'not' infinite (see Captaindoggles post for a reason), in some aircraft a vertical dive will not even reach Vne.

since when did lift oppose drag?, lift opposes weight and thrust opposes drag, lift actually adds to drag because lift generates induced drag, if you fly at 'zero lift' then there is no induced drag.

Like the one in my hanger???

Ohh!....a thorp t18....that's gotta be one of the ugliest mothers I've ever seen.

That passenger is Col. Phil Lacey.

Col. Lacey flew P-40's, P-39's, and P51's with the 8th USAAF in World War II. In Korea he flew F-86's and Vietnam, Canberra bombers.

You don't what aerobatics is until you seen Phil take the stick, LOL. That old man can fly the paint off an airplane.

And yes, he reads and abides by the Operating Notes.....

Is this supposed to convince us you know what you are talking about? because I'm even less convinced of that now.

[Glider]

A couple of obvious points,
1) if you are in a verticle dive then you are already going 150 + or will be in seconds so there is no delay
2) gradual will be smoothly for obvious reasons you dont want to exceed VNE or hit the ground, its a balance.

And we still don't have any accidents the acid test of fragility

PS please show me where is says that a high speed dive is generally the result of a spin recovery

[IvanK]

"Spin training, upset, and unusual attitude training is essential to a fighter pilots core mission."

Actually Crumpp I think you might find that in EVERY current front line fighter deliberate spinning is prohibited !

Upset and unusual attitude training is in fact an essential requirement for every pilot, its mandated for Instrument ratings (in most countries). These terms were not used in WWII and are relatively recent terms.

As for spin training that should imo be mandatory as well ... sadly however it has been removed from the basic syllabus in a lot of countries.

As to this importance being placed on 150MPH before attempting recovery ... baloney !! that is a typical academic approach (as is this entire thread !) to the written word. Its in there to provide guidance to the lowest common denominator. As we all know after recovering from an unintentional spin, its simply a matter of getting your s... in one pile then smoothly recovering from the dive ... no magic just normal piloting to not depart the thing again. Its just like the 90degree nose down at low level scenario (you know the one you didn't want to be in in an aeroplane with stability issues) I suggested earlier .. you going to wait for 150 and risk hitting the ground or get on with your pilot stuff and "Fly the aeroplane" !

We should be able to crack the 1000post mark on this "never ending story" soon... just 100 posts to go.

By the way where is the in game test data in in Ver 1.08.18956 to support your bugtracker entry ?