F-16 best glide speed

[RockyMnt1]

I was watching "Real TV" the other night and they showed a clip of an F-16 losing an engine and gliding to a landing. The airspeed was held at around 208 kts during the glide. He had some external fuel tanks hanging of the wings which he eventually dropped when he got below the cloud deck so as not to hurt anyone on the ground.

Even at 208 kts, this guy was sinking like a rock!!! Is this really the best glide speed of an F-16??

Yikes, that was a shock to this civilian pilot.

 

[FSIGRAD]

Best glide is not actually a set speed, it is an angle of attack. In training aircraft we use a standard best glide speed because the weight of the aircraft does not vary to a large extent. (The change in best glide of an arrow at maximum gross compared to 1 pax and empty tanks is only 2 knots.) The best glide in the POH is for max gross.
For something like an F-16 which carries a large ordinance load I would assume they would determine thier "best glide speed" using an angle of attack meter in the cockpit?

I'm sure some military guys on the board can give the correct answer.

 

[jetdriven]

QUOTE]For something like an F-16 which carries a large ordinance load I would assume they would determine thier "best glide speed" using an angle of attack meter in the cockpit?[/QUOTE]

if it were my F-16 I think I would dump the ordnance!![

 

[Toro]

I can't answer for an F-16, but I can throw out some info for an F-15. We don't have to worry about best glide speed like a viper does since its rare that one of our engines flames out, let alone two, and if they both flamed out we would have to eject. However, our best glide speed would equate to our best lift over drag coefficient. For the F-15, this is going to be 17-18 units of AOA, depending on altitude. The airspeed that corresponds to this is going to depend on gross weight of the aircraft (fuel and external stores) and altitude, but should be somewhere around 220-ish knots. With no thrust, this would put you somewhere around a 10 degree nose low descent. The F-16 can glide much better than us due to the fact that it's much lighter. They practice Simulated Flame Out traffic patterns quite a bit to prepare for when the engine conks out on them.

 

[PilotoHalcon]

Hey Toro, I have not flown a real high performance aircraft other then a LR35 and a C550 BUT I believe the best L/D Max as in a AOA value would be the same regardless of the weight or altitude. As far as weight is concerned the AOA would be constant, but the IAS would change to maintain that best AOA. And as far as altitude is concerned the only thing that would change is TAS. As a general rule, aircraft fly off of IAS, or better yet AOA.
j

 

[ExAF]

Flameout/SFO Landing

Here ya go...right out of the checklist (for a block 40/GE 100 engine...and out of date by a few years)

1. Stores-Jettison (if required)
2. Airspeed-210 kts (note...Increase airspeed by 5 kts per 1000lbs of fuel/store weights over 1000lbs. This equates to approx 6 degrees AOA)

Then there's a bunch of other steps until you get in the Flameout Pattern then once the gear are down:
9. Airspeed-200 kts optimum in the pattern (note...Increase airspeed by 5 kts/1000lbs of fuel/stores over 1000lbs) (Additional note...do not let airspeed to decrease below 180kts plus 5 kts/1000lbs of fuel/stores weight over 1000lbs.)

If you were doing an actual flameout landing, you would almost always jettison any external stores/fuel.

So yes, you are going pretty fast and pretty steep. If you were landing out of a straight in versus an overhead pattern, you would be starting your decent when your aimpoint was approx 11-17 degrees below the horizon. The first time you see the SFO pattern it kind of waters your eyes, but after practice, it is kind of fun. Hope this answers your question. Cheers

 

[Toro]

Reply to PilotoHalcon

Yes, in regards to AOA remaining constant with altitude and weight changes, you are right as a general rule of thumb. However, in the F-15E, it differs slightly with altitude. Above 25,000 feet we use 17 units AOA for max endurance and below 25,000 we use 18 units. Similarly, we use 14 units below 25,000 for max range and 14.5 above 25,000.
I didn't say AOA changed with weight, just airspeed. And yes, if we were trying to do some type of glide/endurance/range for gas or other reasons, we would fly AOA, not airspeed.

 

[Draginass]

I would guess that the F-15 would have considerably more drag in an engines-out glide, and hence, a worse glide ratio. Now about gliding a B-1 . . . . . not.

 

[Draginass]

Any F-4 guy will also tell you that with enough power, even a coke machine can fly.

 

[Hugh Jorgan]

Fat chicks too!