improving the 109??

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How much variation in pitch attitude is there in the Eagle? 0 ft / 50,000 ft / stall speed / mach one / etc.

Greyman,

Gear & flaps down at approach speed in level flight 6 degrees aircraft nose up (ANU). No flap 9 ANU. Speed there is 155-170KIAS. Touchdown is about 135-150.

The heavier you are the more ANU you will encounter. The basic empty weight of an F-15A/C is approx 35k. With a full fuel & weapons load it's about 61k.

At FL500 and sub sonic I think ANU would be approx 3-5, and super would be 3 or less.

The word stall when fighting really never gets used. I have seen 60 ANU at 65KIAS in a clean A, and CLIMBING. God I loved flying that plane! Swept wing fighters usually have control authority of some kind well below 100KIAS. In the Eagle when the stick gets to the seat, you leave it there then start using the rudders and or throttles.

The A/B was my favorite. It was like an 18 year old nymphomanic, eager to please and very responsive. The C/D was like her 35 year old sister. Still fun but requiring much more coaxing...

Cheers,
Biff
 
Here is how top RNZAF ace Wingco flying Evan Mackie described such a lateral turning fight with a FW 190D.

"One particular combat with a long-nosed FW 190, took place at 3,000 ft on a clear day, uninterrupted
by either flak, or other aircraft. Using +11lbs boost & 3,750 rpm the Tempest would almost get into a
position to fire after about 3 complete turns, when the Hun ( sic) would throttle back completely &
disobey the golden rule of not changing bank, by stall turning the opposite way, thus almost meeting
the Tempest head-on or at at least at a big angle. Thus the Hun made a very elusive & formidable target,
for executing this manoeuvre for the 4th time, he managed to take a big deflection shot at the Tempest
as it went steaming past.

The Tempest makes a bigger orbit than the FW 190 but at about 220 mph it competes the actual turn
quicker. After each of these stall turns, the chase would start afresh, the Hun making several unsuccessful
attempts to dive away. After about 10 minutes of this, a pair of Tempests appeared on the scene &
distracted the Hun's attention sufficiently for a short burst to be given which finished him off."

JW,

Imagine two circles, one large and one slightly smaller. The FW-190 is on the smaller circle while the Tempest is on the bigger. Small vs large is one component (radius) and the other is who gets around the circle the fastest (rate).

The Tempest could motor around his circle faster than the FW-190, or out rate him. It sounds like the Tempest pilot had quite a bit of room between him and his adversary, which when the FW-190 "snap rolled", allowed him gain a momentary offensive position at least once. The good pilots know when to break even golden rules and use it to their advantage. Or they realize that damn near all rules have caveats.

Cheers,
Biff
 
At FL500 and sub sonic I think ANU would be approx 3-5, and super would be 3 or less.

So the gun datum being up from the line of flight isn't a correction of any kind - sounds like the difference would certainly be noticeable.
 
So the gun datum being up from the line of flight isn't a correction of any kind - sounds like the difference would certainly be noticeable.

Greyman,

The gun is in the right wing root about 6' off centerline. It's electrically activated (DC power) and hydraulicly powered and fires at a cockpit selectable rate of 3 or 6k rounds per minute. It's canted up 2.5 degrees and towards the left such that the bullets cross the nose over 2k feet in front of the plane. With a radar lock and under heavy G the gunsight will even compensate for flex in the fuselage. 940 rounds roughly equates to 9.4 seconds of trigger time. All courtesy of MacAir and GE.

The Eagle first flew in the early 70's, started sitting 24/7 alert by the mid 70's. I've sat alert in it here in the US, at Keflavik (the only US fighter that sits there in the winter), and in the Middle East. It still sits alert in the US and other places to this day. Kill ratio is 104 to Zero to which I have contributed none...

The F-22 is totally badass and won't even work up a sweat killing Eagles in a 2 vs 8 scenario. However it has some big shoes to fill over time as the Eagle set the bar high.

All from guys with slide rules and imagination!

The up canted gun allows less lead when firing, all to help keep the guy from going under your nose (sound familiar?). It's unnoticeable when employing the gun.

Cheers,
Biff
 
Not precisely what you are referring to, but an anecdote comes to mind;

Two days later on a similar type of sortie, after encountering no opposition, I dived the Wing to eight thousand feet and did a circuit or two over a fighter base near St. Omer. As I circled the field, I saw a lone Junkers 87 taxiing out on the main runway. To my amazement, he turned into the wind and took off. Initially, the pilot must not have known that we were above him. As soon as he was airborne, he must have switched on his radio and been warned of our presence by the Ground Station. He did a very sharp turn and attempted to come in to land again. Claude Weaver was leading Yellow Section of 421 Squadron and at that moment was inside me and below as I circled the field. His request to attack the Stuka was granted. As the Stuka leveled off to touch down, Claude's cannon shells were exploding all around him on the runway. Understandably, he went around again. Twisting and turning, the 87 was chased by his pursuers away from the airdrome while I circled above him at three thousand feet. The Stuka pilot gave an admirable performance of defensive flying against overwhelming odds and just over the top of the ground turned inside his pursuers repeatedly as they attacked. Ignoring my feeling that his performance had earned him a chance to live, I called Claude Weaver and said:

'Yellow One, if you guys don't put that fellow out of his misery in another minute, I'll go down and do it for you.'

My message had been like waving a red flag to Weaver. Leaving the rest of his Section to keep the Stuka busy, he dived away from him on the treetops and came back at him from below. Attacking on a tangent to the Stuka's orbit for the first time I saw cannon shells exploding all over the aircraft. As though in slow motion the Stuka, pouring smoke, sliced into the ground with his port wing and, with his engine on fire, ground along in a cloud of dust. Claude Weaver reported that at the very last, the pilot stood up, the cockpit a cauldron of fire. He put him away with a merciful burst of machine gun. The Stuka pilot had gained the respect of everyone, but the time in the War had passed for chivalry - Hitler had one less pilot for the final battle.


- Wing Commander Hugh Godefroy DSO, DFC and Bar, Croix de Guerre with Gold Star (Fr)

In bold, the true (horrific) cost of war. :(

I love debating and discussing air combat as much as anyone, but there's always that human factor/cost we sometimes tend to forget. And in this case, not just the Stuka pilot. I wonder how Mr. Weaver felt years later about it.
 
I wonder how Mr. Weaver felt years later about it.

Unfortunately Weaver was shot down 28 January 1944. He was killed when his parachute caught on his tailplane and he was dragged to the ground. But I see your point.

The man giving the quote (Godefroy) once strafed a German dispatch rider reading his map in Normandy. The soldier saw him coming at the last second just before he opened fire and raised his arm to shield himself. Godefory said that 'pathetically human gesture' haunted him for the rest of his life.


The up canted gun allows less lead when firing, all to help keep the guy from going under your nose (sound familiar?). It's unnoticeable when employing the gun.

Interesting to hear, since I'm stuck in a WWII mindset. I forgot to take into account the fact that modern fighters don't have to 'fly with the gunsight' like WWII aircraft did - and that modern gunsight pipers generally don't point straight down the line of flight.
 
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Interesting to hear, since I'm stuck in a WWII mindset. I forgot to take into account the fact that modern fighters don't have to 'fly with the gunsight' like WWII aircraft did - and that modern gunsight pipers generally don't point straight down the line of flight.


Greyman,

Actually without a radar lock it acts very similar to the standard gyro compensated gun sight of WW2 fame. Assumptions are built in, and ranging is done using the Mk1 eyeball and or stadiamtric ranging off the recticle size in mils. Once you get good at it you have a good feel for where to put your adversary in the HUD before you squeeze the trigger, and I squeezed whether the lock had settled or not (radar locks can be broken, run off, or take valuable seconds to settle). It's better to have API and his buddy HEI going down range to give him (the adversary) something other to worry about or maneuver to avoid.

Cheers,
Biff
 
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Do you know if canting the gun up a few degrees is a common practice in most modern designs?

I have a lot of WWII documentation of the British trying to solve the problem of only having a 3 - 4 degree 'fighting view' over the nose of their fighter aircraft. Naturally they quickly saw the easy solution of pointing the guns up a few degrees - but in the end were dead-set against the practice due to the obvious dangers when ground strafing or fighting enemy aircraft at very low levels.

Hearing about the Eagle's cannon and lack of nose-down attitude near the ground - perhaps the danger, as seen by WWII RAF officials, was miscalculated. It certainly seemed intuitive to me.
 
Greyman,

F-15 and F-18s do. Do not know of any others. Strafing is doable as the Eagle and Hornet both do. When the Eagle was designed the slogan was not a pound for air to ground. Of course that didn't completely work out, then the Strike Eagle production started and the rest is history.

From the footage I've seen most gun shots from WW2 were low aspect (angle off tail of adversary A/C). Today those are the hardest shots since that is the lowest visual profile and ranges have increased.

Cheers,
Biff
 
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From the footage I've seen most gun shots from WW2 were low aspect (angle off tail of adversary A/C). Today those are the hardest shots since that is the lowest visual profile and ranges have increased.
Cheers,
Biff

That is certainly the case for most successful attacks, and those are the ones for which the camera footage mostly survives. WW2 pilots of all nationalities struggled to estimate their angle off and range which obviously made hitting anything rather unlikely.
The introduction of gyro gun sights did improve gunnery generally, and certainly any sort of deflection shooting.
I did a quick analysis of the average ranges at which pilots (both US and UK/Commonwealth) claimed to have started and finished an engagement. The average at which they opened fire was about 350 yards, and weighted by a few acknowledged long shots. They often broke off at extremely close range, 50 yards appears in some reports.
Cheers
Steve
 
Just a thought, if an attack was a high deflection shot would the target appear on screen or just tracers firing into an open sky?
 
Just a thought, if an attack was a high deflection shot would the target appear on screen or just tracers firing into an open sky?

Generally speaking that would be more a case of how many 'G's the shooter was pulling. But yeah, the more 'G's being pulled the quicker the rounds are going to disappear off the bottom frame.

EDIT: perhaps not so much 'G's as rate of turn. With a 500 mph 'five-G' shot vs. a 200 mph 'four-G' shot ... I'm bad at math but I bet the latter shot would have the rounds move out of frame faster.

Or more accurately - have your gun camera diverge away from your fired bullet paths.
 
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Greyman you are correct in your assumptions. G is usually synonymous with rate of turn except in rare instances (nose falling through the back half of a loop or when aircraft is a falling leaf).

Gunshots today are at a much greater range and in training the minimum range is 500' in most cases. I think this is due to the closure problems a defender can hand the offender and reaction time. I have been inside the 500' bubble while fighting on an occasion or two and I sucked up some serious seat cushion. I have also flown with some bubble violators and that is equally uncomfortable (whether as the offender or defender).

The three rules of gun employment are: in range, in lead and in plane. In range means inside the tactical limits of your weapon. In lead is your nose in front of where he's going. If you have shot skeet it's the same. The best way I can explain in plane is this. Imagine a line coming out of the defenders nose. If he is flying straight (up, down, or level flight) then his line is straight. If he is turning its turning and is basically going where he is going. The offender then must make his line cross or lay on top of the defender. The offenders wings do not have to be parallel to the defenders.

Once the above conditions have been met you can squeeze the trigger, however you need to be cognizant of your range and closure, AND if you miss the goal is to not to overshoot or be forced into a role reversal. The stick movements when employing the gun are very smooth in order to keep the pipper on the target. No pulsing the stick when squeezing the trigger. However, should you miss the reposition can be very abrupt with full stick and or rudder.

Cheers,
Biff
 
That is certainly the case for most successful attacks, and those are the ones for which the camera footage mostly survives. WW2 pilots of all nationalities struggled to estimate their angle off and range which obviously made hitting anything rather unlikely.
The introduction of gyro gun sights did improve gunnery generally, and certainly any sort of deflection shooting.
I did a quick analysis of the average ranges at which pilots (both US and UK/Commonwealth) claimed to have started and finished an engagement. The average at which they opened fire was about 350 yards, and weighted by a few acknowledged long shots. They often broke off at extremely close range, 50 yards appears in some reports.
Cheers
Steve
wiki- on Hartman
His favourite method of attack was to hold fire until extremely close (20 m (66 ft) or less), then unleash a short burst at point-blank range.

During the course of his career, Hartmann was forced to crash-land his fighter 14 times due to damage received from parts of enemy aircraft he had just shot down or mechanical failure
 
Just a thought, if an attack was a high deflection shot would the target appear on screen or just tracers firing into an open sky?

It depends. There is plenty of footage from fighters making quarter and other attacks with deflection (even beam attacks) on bombers, which are essentially flying straight and level, and because the fighter is flying a gentle pursuit curve the target is always visible and in the sight despite the relatively high angle off. It is all about relative angles and positions.
There is an RAF gunnery manual called "Bagging the Hun" which includes a lot of illustrations of what an attacking pilot would expect to see, many in the form of problems for which the reader is expected to estimate range and angle off. If you can find a copy (and I've seen it online) you can find out just how bad you would have been at making the estimates! I was truly awful.
Cheers
Steve
 

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