F-16 suvivability, et al

Salute

As promised in the 9-gee thread, here's some insight as to why the Viper would be and has been very good in combat. Pic is below.

On a snowy day in 1983, I took off in a formation to act as the 'bandit' for 'Joe Baggodonuts" in the B-model in front of me.

Just as gear came up, the plane rolled to the right and I felt a pronounced buffet/shudder. Thot it was jet wash from lead. Didn't realize how much left stick I was holding, as in the Electric Jet, the stick moves about 1/8 inch (Block 5 and later). Look left, no problem, look right - holy s$%#)

Right leading edge flap was up at about 60 degrees or so.

Followed golden rule: maintain aricraft control. Then analyze the situation and take corrective action. Heh heh. I was about to join Yeager as a test pilot pressing the envelope.

Turns out that two careless troops had forgotten to insert a 'keeper pin' in the flap rotary tube mechanism at the wing root. The spline on the large drive tube gradually worked itself loose and zhazzam! Didn' know this at the time and frankly, Scarlett.....

Pulled up, bunted over to get other LEF up at 2 degrees, then locked the flaps. Figured I may as well have them closer together as far as angles.

Flew around skidding like crazy and managed to get lined up on runway. Only 7 or 8 minutes, so I didn't feel real tired holding left stick. All I knew was that I was holding damned near all I could left and if I relaxed, the thing rolled right - a lot! They later told me that I was holding about 15 pounds. As the max roll command was about 16 or 17 pounds, I didn't have a lot to play with.

Got the bird aligned with the rwy and plopped it on. I was flying about 40 knots above normal speed, as it got flaky any slower and I wasn't going to 'explore' the envelope. If I could fly it at 170-180 knots, then 'works for me'.

The plane slowed so quickly when I pulled power off that I barely made the end on the runway. Drag quite high, if you see the pic of that flap. Once on terra firma, rudder worked well and I slowed very rapidly, even making a mid-field turn off.

- the FLCS maintains zero roll rate if hands off the stick. So I prolly had a fair amount of left roll command without 'helping'. Nevertheless, the shape of the curve used to actually position the flaperons and the various air data and body rate inputs allows 'extra' input from the pilot.

Any other jet would have rolled right and 'poof'. So old FLCS gave me a head start.

- the F-16 hydraulic actuators are all in the fuselage. So the bandit can shred your elevators and wings, but stuff keeps moving. This is a good survivability feature. No hydraulic lines to bleed out in the wings or tail if you get hit.

In case of the LEF's, the hydraulic motor connects to a large drive shaft right at the wing root. It was this connection that failed. Hence the entire LEF folded up until it reached the top skin of the wing. Another troop had it happen to him a few months later at 300 knots and the LEF was just about vertical. He got it on the ground ( word from my episode and techniques had finally gotten around).

Lemme tellya. If a plane can fly around with 25% of his wing folded up, then a few holes and dings shouldn't hurt too badly, huh?

later,

What happens when your LEF blows to 60 degs up? You get an LES!

Leading Edge Spoiler

Had something similar happen during a DBFM break turn...

Cylon

and theeen? .......

Turns out that two careless troops had forgotten to insert a 'keeper pin' in the flap rotary tube mechanism at the wing root. The spline on the large drive tube gradually worked itself loose and zhazzam!

Yes it is a survivable jet, until the engine quits. I have seen horrific formation mid-air damage on F-15s and F-18s that limped home that in the same situation, the F-16 guy would be walking home. Also thank goodness for todays modern PGMs. This jet going though flak that beats up an A-10 would not be the way to go. SAMs and FLAK are the main threat to this jet as history shows. WCMD, LGBs, JDAM, SPICE, HAVE LITE, etc, means in many cases; I can touch you, but you can't touch me. After all that, I believe the early F-16s in their time were the best light day bombers (with dumb iron) period.

Yepper, ELP, good points.

Back in the A-9 and A-10 flyoff, we mudbeaters argued about the survivability issue and the best way to proceed.

I personally got in trouble for advocating that the plane that doesn't get hit doesn't need all the armor. I also advocated a good computer delivery system that I had lottsa combat experience with - The one in the A-7D and A-7E. My previous combat tour was in the A-37. It was pure manual, and about as simple as it gets.

So the tradeoff came down to a) get hit, but survive b) don't get hit 'cause you could drop higher/faster and more accurately than the guys with the dumb systems.

Go back to the experience we were using. The Double Ugly, Thuds and F-100's were dropping from high alt and going really fast. The A-1 and A-37 and T-28, et al were getting 'down among them'. Sure, we could bomb real good, but we got hit. What we needed was a mix of the survivability and the accuracy.

The F-16 used all the lessons from the A-7D and A-37. A super bombing system and the speed/small size to reduce chances of getting hit. Further, as all the hydraulics were in the fuselage, the standard pings on the wings, flaps, 'vator, etc, didn't really hurt much.

My point in the post is that the Viper FLCS helps a pilot with a wounded bird. Poor suckers flying basic flight control systems, with limited augmentation are at a disadvantage.

With regards to two engines. Combat losses due to engine losses for multi-engine fighters versus single-engine ones is not all that significant as one might believe. When the 85 mm shell hits your jet's fuselage, don't make much difference about number of motors. Same for a fire.

There are tradeoffs with respect to engines, basic structural strength, back-up systems, etc. Then there's the tactical considerations. Wanna get down close and root around or stay high/fast and still hit the target?

My main point is that the basic airframe design and FLCS of the F-16 provides very good chances of surviving a missile hit or ack hit and still make it home. The development of the JDAM and other new weapons makes a lot of planes more survivable. Hell, a Cessna 172 could drop a JDAM from 10 miles away and it would hit the same as if dropped from a F-15E.

As ponted out, ack and SAM's seem to be the biggest threat, not other fighters. Same in WW2 and in 'nam. So I want a bird that can fly with the leading edge flap up at 60 degrees, or a missing stabilator or aileron or chunk of a wing blown to hell. I also don't want to have to fly at 300 knots and get low to ensure accuracy (ala A-10).

Thanks for feedback, and we can continue with many war stories, personal opinions, etc. Much as we did in early 70's.

later,

Hell, a Cessna 172 could drop a JDAM from 10 miles away and it would hit the same as if dropped from a F-15E.

Gums, I'd love to know the time to climb and range of a C-172 with a 500lb JDAM, let alone a 1000lb or larger!

Seriously, I agree with most of your points. The loss of any aircraft depends more on what is hit, rather than how many engines you have. Having two engines does provide a slight more redundancy, but at greater maintainance cost as well...

Kevin
The Ejection Site

kmceject wrote:

Hell, a Cessna 172 could drop a JDAM from 10 miles away and it would hit the same as if dropped from a F-15E.

Gums
Having two engines does provide a slight more redundancy,

Its also really reasuring when you look down and see nothing but water.

A-7 was a great day bomber too. I believe it upset the F-111 guys in tac bomb comps more than a few times.

Ok, aircraft survival it all depends on where it got hit, or what is falling apart. As far as two engines, so long as your engine doesnt explode or disintegrate. I saw a mishap report where an F-15 engine was eating it's self. The engine came apart and went though the airframe and destroyed the other engine, thus forcing the pilot to call a taxi.

I thought the F-15 had a titanium keel that was supposed to help protect one engine if the other fragged itself. I realize such a barrier isn't a guarantee, but is there such a Ti keel in the -15?

Sorry guys, but I want to see an F-16 landing only with one wing

DeepSpace wrote:Sorry guys, but I want to see an F-16 landing only with one wing

I would like to see any airplane land with one WHOLE wing missing, parts of it sure, but the whole thing, I don't think so. If you remember the F-117 that lost its wing at an airshow, it clearly didn't do well, and it has two engines.

I would like to see any airplane land with one WHOLE wing missing, parts of it sure, but the whole thing, I don't think so. If you remember the F-117 that lost its wing at an airshow, it clearly didn't do well, and it has two engines.

http://www.f-16.net/modules.php?op=modl ... 155&page=1
Visit the link for pictures.



On may 1st. 1983, a simulated dogfight training took place between two F-15D's and four A-4N Skyhawks over the skies of the Negev. The F-15D (# 957, nicknamed 'Markia Shchakim', 5 killmarks) was used for the conversion of a new pilot in the squadron. Here is the description of the event as described in "Pressure suit":
At some point I collided with one of the Skyhawks, at first I didn't realize it. I felt a big strike, and I thought we passed through the jet stream of one of the other aircraft. Before I could react, I saw the big fire ball created by the explosion of the Skyhawk. The radio started to deliver calls saying that the Skyhawk pilot has ejected, and I understood that the fire ball was the skyhawk, that exploded, and the pilot was ejected automatically.

There was a tremendous fuel stream going out of the wing, and I understood it was badly damaged. The aircraft flew without control in a strange spiral. I re-connected the electric control to the control surfaces, and slowly gained control on the aircraft until I was straight and level again. It was clear to me that I had to eject. When I gained control I said : "Hey, wait, don't eject yet!". No warning light was on and the navigation computer worked as usual; I just needed a warning light in my panel to indicate that I missed a wing..." The instructor ordered me to eject. The wing is a fuel tank, and the fuel indicator showed 0.000 so I assumed that the jet stream sucked all the fuel out of the other tanks. However, I remembered that the valves operate only in one direction, so that I might have enough fuel to get to the nearest airfield and land.

I worked like a machine, wasn't scared and didn't worry. All I knew was : as long as the sucker flies, I'm gonna stay inside. I started to decrease the airspeed, but at that point one wing was not enough. So I went into a spin down and to the right. A second before I decided to eject, I pushed the throttle and lit the afterburner. I gained speed and thus got control of the aircraft again. Next thing I did was lowering the arresting hook. A few seconds later I touched the runway at 260 knots, about twice the recommended speed, and called the tower to erect the emergency recovery net. The hook was torn away from the fuselage because of the high speed, but I managed to stop 10 meters before the net.

I turned back to shake the hand of my instructor, who urged me to eject, and then I saw it for the first time - no wing !!!

The IAF contacted McDonnel Douglas and asked for information about possibility to land an F-15 with one wing . MD replied that this is aerodynamically impossible, as confirmed by computer simulations... Then they received the photo....

After two months the same F-15 got a new wing and returned to action.

Written by: Tsahi Ben Ami

This is what "Flight international, 8 June 1985" wrote about the incident :

"The most outstanding Eagle save was by a pilot from a foreign air force. During air combat training his two seater F-15 was involved in a mid air collision with an A-4 Skyhawk. The A-4 crashed, and the Eagle lost it's right wing from about 2ft. outboard. After some confusion between the instructor who said eject, and the student who outranked his instructor and said no, the F-15 was landed at it's desert base. Touching down at 290 kt, the hook was dropped for an approach and engagement. This slowed the F-15 to 100 kt, when the hook weak link sheared, and the aircraft was then braked conventionally. It is said that the student was later demoted for disobeying his instructor, then promoted for saving the aircraft.

McDonnel Douglas attributes the saving of this aircraft to the amount of lift generated by the engine intake/body and "a hell of a good pilot".

Written by: Tsahi Ben Ami

Ok, so now I have heard of one aircraft that landed succefully with one wing. Could it be repeated, succesfully? I doubt it, though it proves that with enough thrust you can make anything fly.