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In the late 1980s the Combat Core Certification Professionals Company acquired a number of MiG-15s and MiG-17s from China and Poland. The aircraft were employed in a "mobile threat test" at Kritland AFB. At the time the Pentagon's Office of Operational Test and Evaluation intended to acquire enough equipment to simulate two Soviet air defense regiments!

Any one know which aircraft were involved and where they are now ?
Be lucky
David

Chris,

Sorry it has taken me so long to reply to your post but I don’t get on the forum quite as much as I use to.

Once again, it's been 30 years now since I've flow the F-4 but let me dig around in the memory bank and see what I can remember.

All F-4s had an aural AOA warning system installed. The hard wing F-4 as I recall, minimum drag (around 0 G) was 3-8 units AOA. Optimum turn (a turn you could perform without losing airspeed) was around 11-13 units AOA, and maximum lift was defined at 19.2 units. These "units have nothing to do with degrees; they were just "units of measurement". The aural system started with slow "beeps" around 17 units, went to a steady tone at 19.2 units, and a loud, shrill beeping noise at 21 units and above. There was also an AOA indicator light system up by the windscreen that corresponded to the aural warning system (fast, on-speed, and slow lights). The pedal shaker came on around 25 units and was intended as a warning to move the stick forward to reduce the AOA before the plane stalled and departed controlled flight. 19.2 unit hard turns (we also flew final approach at 19.2) was relatively smooth with little of no buffet. Buffet occurred around 21 units and above. The transition from aileron to rudder started around 15 units (well before buffet or pedal shaker) and by 19.2 units the ailerons were normally not used at all and almost all the roll was with the rudder.

The F-4E LES (slatted E) was different than the hard wing. It turned better than the hard wing but it had more drag and it bled airspeed faster that the hard wing. I think we still flew final approach at 19.2 units but in the air, maximum turn was defined at 25 units AOA. Although we still used mostly rudder at high AOA (probably starting around 20 units) some aileron could be used. “Adverse Yaw” caused by the down aileron was not as pronounced in the “slat” as the hard wing. The lift curve in the slatted E did not drop off if we exceeded 25 units AOA.  Lift continued to increase but it increased at a very low rate and since the drag curve above 25 units increased very abruptly, 25 units was “selected” to represent the “maximum” AOA.

As I recall we did use the rudder quite a bit in the MiG-21. Especially when we went from a hard turn and as the airspeed bled down, into the loaded-up, high AOA reversal (with flaps down) forcing an overshoot by the attacker. These reversals almost always succeeded into getting the attacker at least line abreast with the MiG-21 (scissors territory) and many times out in front of it. The MiG-21F could fly all the way down to around 73-77 knots before it would stall (depending upon weight/fuel on board) and if it did stall, all that would happen was the nose would drop toward the horizon and it would fall off on one wing. By that time, you had 100-120 knots again and you could pull the nose back up and continue the “scissors” maneuver (slow speed flight).

You asked about using rudder in the F-14. Being an Air Force guy, I didn’t fly the F-14 so you’ll have to ask one of the Navy guys that question.

Thanks for the information on sideslip at high AOA and the washout of the vertical stabilizer on the MiG-23. I’m not sure I knew the specifics of that when I was actually flying the airplane but we certainly knew we had to be very careful at high AOA. I’m not sure if this was addressed in the “Have Pad” report or not.

I hope this answered your questions.

Ted

Hello Ted,

thanks for your reply!

First, let me start by saying it has now been over 23 years since I flew the MiG-23 but I’ll tell you what I remember about the rudder in it and the F-4 at high AOA.

I do very much appreciate your help and your contributions. This forum is probably one option to preserve your experiences and informtation for others.

Let’s start with the F-4. During high AOA maneuvering in the F-4, if you used the stick to roll left (for example), the right aileron would go down to try to produce more lift on the right wing to get the aircraft to roll left. But at high AOA, the down aileron on the right wing produced so much drag that the F-4 would actually yaw to the right (we called it “adverse yaw”). The right yaw caused the left wing to produce more lift and the aircraft would actually roll to the right (opposite of what you intended). So as the stick came back and the AOA increased, we phased out the use of ailerons and phased in the use of rudder to produce yaw and roll in the intended direction.

Increasing buffeting and the pedal shaker gives your clear warnings when to start using the rudder, right?
Was there much difference between the "hard winged" and "slatted" F-4?
It is interesting that this was opposite to the MiG-21. At least this was told to me by former MiG-21 pilots (one of them later flew F-4F Phantom). You should avoid using rudder during high AoA maneuvering at low speed. Did you have the same experience with the MiG-21?

The MiG-23 has no ailerons. It rolls with spoilers and differential horizontal stabilizer/stabilator. As the wings move from 16 degrees to 72 degrees the wings actually move partially into the aircraft fuselage and the spoilers are automatically phased out so they don’t damage the fuselage. The end result is that at 72 degrees, all spoilers are phased out and the roll comes solely from the differential stabilizer (which worked great). At 45 degrees wing sweep, it rolled will partial spoilers and the differential stab. So if you wanted to roll left at high AOA, as you moved the stick to the left, the spoilers on the left wing would come up to kill some of the lift on the left wing and along with the differential stab, would cause the aircraft to roll left. Any drag caused by the up spoilers on the left wing (very slight) would cause some yaw to the left which would aid the intended left roll and not hinder it like the F-4 did due to its “adverse yaw”.  So you can see in the MiG-23, there was not the need for a complete transition to rudder at high AOA like there was in the F-4. Having said that, I do seem to remember using some rudder to coordinate the rolls but nothing like we used in the F-4.

True. The yaw caused by the drag induced by the up-spoiler aids to the roll.
However, the huge differential stabilizer, which hold a big portion for rolling at 45° wing sweep, generating a strong side moment. This also causes the aircraft to adverse yaw while rolling at higher AoA at low and medium speed. It was the first time for the MiG engineers implementing a differential stabilizer with a serial production aircraft and this was the main reason for sudden departure already at non-critical AoA. It was very different to the MiG-21 and they discovered that after a series of accidents and unfortunatly fatal crashes.
They introduced an interconnect between rudder and differential stabs (aileron-rudder-interconnect), which counter the sideslip. That is why I ask you about the use of the rudder.

It might be interesting to note that they learned the lesson. The MiG-29, which is using a combination of ailerons and differential stabilizer to roll, also has an aileron-rudder-interconnect and additionally automatically phases out the differential mechanism of the stabs during high AoA leaving the roll control to the ailerons and rudder.

The F-14 has similar roll controls like the MiG-23. You have the spoilers and differential stabs. How did you use the rudder here while rolling at high AoA?

The only aircraft we could sometimes turn with was the F-4 and even that wasn’t done very much because our penalty in the MiG-23 for exceeding the AOA limits was much more severe than the penalty in the F-4. The F-4 would depart controlled flight but could be recovered very quickly with forward stick and it almost never spun. When the MiG-23 went out of control, it almost always spun and was more difficult to recover (and a spin in the MS model usually also resulted in engine damage as has been discussed earlier on the Constant Peg Forum.

True. The MiG-23 gives none or little warnings (e.g.buffenting) before stall occures and it had an unpleaseant and very dangerous feature. When you exceed a certain sideslip at high AoA the vortex flow (Vortex generated at wing glove leading edge.) crosses the MiG-23's back, washing out the vertical stabilizer. You can see that in the picture attached.
As a result the plane is immediately losing all the directional stability and snap-rolls and spin with little or no chance to recover.
It took them (the developers and engineers) a while to discover the reason to that and they did a lot of spin research with the MiG-23 to cover that.
For me you experiences fully seem to support this.

Finally they implemented the SOUA stick stop device to prevent exceeding the AoA limits and the afore mentioned aileron-rudder-interconnect to avoid the sideslips during high AoA excursions with the Flogger-B and Flogger-G. This and some other changes considerably improved the AoA handling and turn capability of the MiG-23.

Chris

The patch was made for the Aggressors in the late 1980s. The MiG-29 Fighting Fulcrum patch that was a play on the F-16 Fighting Falcon patch was done at the same time. The patches had nothing to do with actually flying the aircraft, only emulating them; which the F-5 could not do very well. Of course, the Fighting Fulcrum patch was adopted by the Luftwaffe Fulcrum squadron. The flag colors were changed to the German colors and a Maltese cross was place in the middle of the flag.

Chris,                        22 Aug 2010

   First, let me start by saying it has now been over 23 years since I flew the MiG-23 but I’ll tell you what I remember about the rudder in it and the F-4 at high AOA.
   I assume you are most interested in the 45 degree wing sweep position. The only thing we used 16 degree wing sweep for was takeoff, landing and loiter. 72 degree wing sweep was obviously the ‘go fast” position with little to no high AOA maneuvering done there (except demonstrations during transition training).
   So the 45 degree wing sweep position was the only position where we ever did high AOA maneuvering (and we didn’t do much there either for reasons I will go into later.
   Let’s start with the F-4. During high AOA maneuvering in the F-4, if you used the stick to roll left (for example), the right aileron would go down to try to produce more lift on the right wing to get the aircraft to roll left. But at high AOA, the down aileron on the right wing produced so much drag that the F-4 would actually yaw to the right (we called it “adverse yaw”). The right yaw caused the left wing to produce more lift and the aircraft would actually roll to the right (opposite of what you intended). So as the stick came back and the AOA increased, we phased out the use of ailerons and phased in the use of rudder to produce yaw and roll in the intended direction.
   The MiG-23 has no ailerons. It rolls with spoilers and differential horizontal stabilizer/stabilator. As the wings move from 16 degrees to 72 degrees the wings actually move partially into the aircraft fuselage and the spoilers are automatically phased out so they don’t damage the fuselage. The end result is that at 72 degrees, all spoilers are phased out and the roll comes solely from the differential stabilizer (which worked great). At 45 degrees wing sweep, it rolled will partial spoilers and the differential stab. So if you wanted to roll left at high AOA, as you moved the stick to the left, the spoilers on the left wing would come up to kill some of the lift on the left wing and along with the differential stab, would cause the aircraft to roll left. Any drag caused by the up spoilers on the left wing (very slight) would cause some yaw to the left which would aid the intended left roll and not hinder it like the F-4 did due to its “adverse yaw”.  So you can see in the MiG-23, there was not the need for a complete transition to rudder at high AOA like there was in the F-4. Having said that, I do seem to remember using some rudder to coordinate the rolls but nothing like we used in the F-4.
   Now that I’ve talked a lot about high AOA maneuvering, let me say we didn’t do much of that in the Mig-23 because that was not its strong suit. Most of our missions were against out front line fighters of the 1980’s (F-14, F-15, F-16, F-18) and although we demonstrated the MiG-23’s turn capabilities in the “Performance Profile” mission, during the tactical missions we usually used hard turning very little and going fast a lot. Getting into a hard turning, high AOA maneuvering fight against any F-14, F-15, F-16, F-18 always resulted in the MiG-23 being killed very quickly. The only aircraft we could sometimes turn with was the F-4 and even that wasn’t done very much because our penalty in the MiG-23 for exceeding the AOA limits was much more severe than the penalty in the F-4. The F-4 would depart controlled flight but could be recovered very quickly with forward stick and it almost never spun. When the MiG-23 went out of control, it almost always spun and was more difficult to recover (and a spin in the MS model usually also resulted in engine damage as has been discussed earlier on the Constant Peg Forum.
   As for how many departures we experienced in the MiG-23, I didn’t keep records but as I recall, we had a few. I think about one out of every 4-5 or so pilots who flew it experienced a departure and spin. I don’t know of any one who spun it on more than one sortie. I spun it twice but that was on the same sortie when it departed and spun again during the recovery from the first spin. Looking back at Steve’s book, we had 32 pilots fly the MiG-23 and some of them only flew a few sorties in it. I’d guess we had maybe 6 total departures and spins out of over 3000 sorties so you can see the rate was not very high. Add to that the fact that almost all of our departures and spins were in the BN (ground attack) model because it was not as stable as the MS model since it was not intended to be flown in that environment.

Ted
   

Found this (where else) on Youtube.  Supposed to have been used for briefing main line pilots
http://www.youtube.com/watch?v=reVZ9aPYi9A&NR=1
and their version of Red Hats
http://www.youtube.com/watch?v=GGmBdqxrwbw

The problem with the MiG-23 was it's relatively low AOA limits and the sever penalty you paid if you exceeded them (eg: departure and spin).

Ted,
would you mind to explain the use of the rudder during higher AoA with the MiG-23 (we agree both on the limitations   ), e.g. did you used it to roll the a/c like it it has to be done with the Phantom?!
Did the Red Eagles had other departure or spin related accidents (without crashing the a/c) with the MiG-23?


BTW, I have to correct myself. You and "Flogger Geek" are right about the AoA indicator and the true AoA.

As I recall, the AOA limit was around 17 UNITS at 16 degrees wing sweep, 27 units at 45 degrees sweep, and 32 units at 72 degrees sweep. I stessed UNITS because it was in units and not degrees AOA so I don't know how many degrees that corresponded to.

... AOA signal generated/sensed by
left-side sensor AOA vane transducer. This signal sent through a filter to
provide lead to prevent overshoot. These signals are not corrected for upwash or
sideslip. There are charts to correlate cockpit AOA indications to actual
degrees! .

The indicator does show AoA in degree, but not corrected and only local for the left-sided DUA AoA sensor. Flogger Geek correctly described that. There is a rule of thumb for the MiG-23MS to calculate the correlation between true and local AoA:

 α(local) = 1.6α(true) - 1°

Might be interesting for "Flogger Geek".

Chris

Steve,
Any news on either of the new books yet. My amazon finger is getting itchy.
Thanks in anticipation,
Be lucky
David

Jack Manclark - many thanks for providing a glimpse of another Red Eagle !

Cheers,

Haydn.

Jack's fini photo posted here: http://fjphotography.com/constantpeg/forum/index.php?topic=135.0

Jack also confirmed that there was a stripper waiting for him for his 40th birthday. Now, who has pictures?!