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Old 4th Feb 2017, 08:46
  #101 (permalink)  
 
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Having done spinning in a Chipmunk, I was at first startled at the height the Instructor deemed safe for spinning a Tiger Moth. There are big differences between aircraft in the height needed for safe spin recovery.
And C of G will affect it.
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Old 4th Feb 2017, 10:02
  #102 (permalink)  
 
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"I was once on final in a glider with an instructor, at 400 ft he said "I have!" And spun it losing 200 ft. "You have" he said as two Tornadoes roared overhead at 4/500 ft. I recovered it and landed, along with "what the f**k". So it is possible."

If true, I sincerely hope this instructor NEVER flew again, let alone instructed.
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Old 4th Feb 2017, 10:50
  #103 (permalink)  
 
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Not wishing in any way to dampen a thoroughly entertaining read, but has anyone, witnessed, completed, heard of, a spin recovery, in the circuit, from 500'
I have not. I did witness an airshow pilot attempt to demonstrate a low altitude spin. His attempt was fatal. :

https://aviation-safety.net/wikibase/wiki.php?id=39240

Which left a lasting impression that such maneuvers are foolish
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Old 4th Feb 2017, 11:13
  #104 (permalink)  
 
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Exactly Step. Deliberately spinning at low-level is like practicing bleeding.
Its breathtakingly stupid.
In the glider example cited I don't understand the relevance of the two Tornadoes either. If the instructor's intention was to lose height quickly, a spin is not the correct manuver.
I call bulldust. I was tempted to ask "what sort of glider" but then realized its a moot point, bulldust is bulldust.
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Old 4th Feb 2017, 11:18
  #105 (permalink)  
 
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Originally Posted by Thud105
"I was once on final in a glider with an instructor, at 400 ft he said "I have!" And spun it losing 200 ft. "You have" he said as two Tornadoes roared overhead at 4/500 ft. I recovered it and landed, along with "what the f**k". So it is possible."

If true, I sincerely hope this instructor NEVER flew again, let alone instructed.
I'm afraid I had the greatest respect for that particular instructor.
So did any other pilot in the club.
He was no cowboy, and taught me and many others very well.
He spun the thing as the quickest way to lose height without over speeding, go around not an option. The Tornadoes were on a collision course and hadn't seen us.
Please don't jump to conclusions. It certainly was not done for fun!!
The actual manoeuvre amounted to an upside down nose down rapid loss of 200ft followed by recovery. As we got to about 45deg he handed it back.
It was a K13 glider.
Whether you wish to call it a true spin I really couldn't say, it happened too quickly.
It certainly rotated around its long axis with the nose down. Call it what you like, but bull dust it certainly wasn't.
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Old 4th Feb 2017, 11:21
  #106 (permalink)  
 
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bulldust.
I really like that term. Think I will use it in future when I come across any.......unfortunately, that is pretty frequent.
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Old 4th Feb 2017, 11:53
  #107 (permalink)  
 
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He spun the thing as the quickest way to lose height without over speeding
I'm not a glider pilot, I admit that, 'only flown them a few times (and really enjoyed it!). But I am rather experienced at intentional spin entries. For my experience, a spin can be entered from slow deceleration, which will take planning, patience and time, or, from an abrupt maneuver, which will generally see the required decay in speed as a gain in altitude first. Therefore, as a rapid evasive maneuver to lose altitude, a spin entry would not come to mind. Nose down and a sideslip would....
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Old 4th Feb 2017, 11:58
  #108 (permalink)  
 
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Sorry, I'm not buying it. So, you're on the approach at say 400ft and 55kt in a -13. Want to descend quickly? Full brakes and lower the nose - a 13's brakes are speed limiting. Or, as Step suggests - a very steep side-slip with full airbrake.
The whole thing sounds incredibly fraught - if not dare I say unbelievable. Upside down at 300ft, and then he handed control back........
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Old 4th Feb 2017, 12:10
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Originally Posted by Thud105
Sorry, I'm not buying it. So, you're on the approach at say 400ft and 55kt in a -13. Want to descend quickly? Full brakes and lower the nose - a 13's brakes are speed limiting.
The whole thing sounds incredibly fraught - upside down at 300ft, and then he handed control back........
It wasn't upside down when he handed it back, it was at about 45 deg right side up, still decending and under control.
After the event the instructor called Leuchars military and asked, pretty much, what the hell they were playing at. They denied all knowledge.
At the weekend the two Tornado crews arrived at the gliding club, apologised profusely for an error of "cross a big lake, between two hills, down the valley and turn left". And spent the evening buying the beer.
They picked the wrong two hills and flew over our airfield by mistake.
I remember the incident very well even though it was '85.
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Old 4th Feb 2017, 12:23
  #110 (permalink)  
 
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I believe the event happened. I don't believe you spun at 400ft, or were inverted at 400ft. Either event in a K-13 would, IMHO only end with a crash. Very steep side-slip with full airbrake is the most plausible scenario - IMHO of course.
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Old 4th Feb 2017, 14:43
  #111 (permalink)  
 
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Originally Posted by Thud105
I believe the event happened. I don't believe you spun at 400ft, or were inverted at 400ft. Either event in a K-13 would, IMHO only end with a crash. Very steep side-slip with full airbrake is the most plausible scenario - IMHO of course.
Believe what you wish, I was there you were not, I recall the rotation all the way round rather than a reversal. I do, and did, know the difference between inverted and slipping.
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Old 4th Feb 2017, 15:33
  #112 (permalink)  
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So we're finished with the discussion about Tornado avoidance maneuvering in the K13, one way or the other?
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Old 4th Feb 2017, 15:57
  #113 (permalink)  
 
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Well from my memories of spinning K13 - from annual check flights, were that to get it to spin you needed - for a spin to the right:
Approach the stall speed from straight and level.
Before you reach stall pull the elevator full back (thus gaining altitude) and at the same time apply full left aileron to get the right wing to stall.
While doing this apply full right rudder.
So you entered the manoever holding the stick hard back and to the left with your right leg fully extended to hold the right rudder in.
This would create a sort of flick roll entry which is most cases would then become a spin - though on some occasions if the timing of the control inputs was a little out it would instead enter a spiral dive.

Recovery was the usual opposite rudder while moving the stick forward with ailerons neutral and recover from the ensuing dive.
Notice I said 'while' in the preceding sentence not the usual power aircraft default of opposite rudder wait and then stick forward.
If you held the stick hard back (at my CofG loading anyway) and just applied opposite rudder (left in this case) then the direction of the spin immediately reversed and you would need to apply in this example right rudder again plus stick forward to get it to come out.
I hope this is of some vague interest - if anyone is remotely bothered.........

Last edited by dsc810; 4th Feb 2017 at 16:37.
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Old 4th Feb 2017, 16:42
  #114 (permalink)  
 
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Originally Posted by Thud105
Well, in that case you weren't at 400ft. And I don't need to have been there to know that either spinning or being inverted at that height in a K-13 could only end in a crash, whereas you claim he then "gave it back to you." Note also that - as Step points out - to spin abruptly would require a gain in altitude.
I spent a lot of time in the air as a gliding instructor in the 80s and 90s, which included a fair amount of time in K13s. The K13 has a fairly benign spin which is easy to recover from and it does not lose a lot of height. Certainly one wouldn't deliberately enter a spin to avoid an approaching jet! I believe the instructor in this instance "turned away from the threat" and either pulled too hard and unintentionally entered a spin(unlikely), or conducted a fairly vigorous manoeuvre which became a spiral dive, and that might have felt like a spin. Undoubtedly a very unpleasant experience and there are still too many instance if powered aircraft (civil and military) infringing gliding sites. Whilst they are a hazard to gliders, the 2,000 feet of cable in the air offers a significant hazard to powered aircraft!

Last edited by terry holloway; 4th Feb 2017 at 16:42. Reason: Typo!
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Old 4th Feb 2017, 16:56
  #115 (permalink)  
 
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I remember the incident very well even though it was '85.
I am struggling to find any record of Tornado squadrons at Leuchars as early as 1985.
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Old 4th Feb 2017, 17:14
  #116 (permalink)  
 
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I have always been quite good at recalling details, I was trained to do that in the military. I am also not guilty of elaborating on facts as I remember them.
This manoeuvre did not involve waiting for the stall, followed by what may be considered normal intentional spin entry procedures.
This was a rapid application of left aileron until beyond 90deg followed by a hard pull as the rotation continued, at the point of about 45deg before returning to level and with the nose starting to rise, but still well below horizonal, control was given back to me.
I continued the rest of the roll and nose levelling and then landed.
Perhaps it was not a true spin in the normal sense of climbing stall, rudder, aileron or whatever, followed by opposite rudder, forward stick recovery. But, the aircraft rotated through 360deg around the long axis, lost about 200ft in the process, enough to avoid the threat. I do recall seeing the condensation around the Tornadoes dead ahead.
We certainly lost the height far quicker than any normal upright manoeuvre of dive, side slip, air brakes or stalling would have produced.
Please don't insult my intelligence by telling me I was not inverted but in a side slip instead. And at half a field short of the touchdown point I was not far away from 400ft. Though I am not in the habit of staring at the instruments at that point in the landing process.
Edit: the Tornadoes were crewed by Americans from somewhere else.
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Old 4th Feb 2017, 17:26
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You must be misremembering; the US has never operated Tornado.
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Old 4th Feb 2017, 17:55
  #118 (permalink)  
 
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This manoeuvre did not involve waiting for the stall, followed by what may be considered normal intentional spin entry procedures.
This was a rapid application of left aileron until beyond 90deg followed by a hard pull as the rotation continued,
If the maneuver did not involve waiting for a stall, it was not a spin entry (to be proud of, anyway). If it involved a steep roll and a pull it has the signs of a spiral dive, or some kind of wingover.

It is very important for pilots to recognize and correctly react to one vs the other, in recovery. The recovery for one, applied to the other situation, could be messy. I accept that the other pilot flying the glider flew a purposeful evasive maneuver (which worked), but as I understand the description, if that pilot was asked if they had deliberately spun the glider, I doubt that answer would have been yes.
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Old 4th Feb 2017, 19:29
  #119 (permalink)  
 
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Crash one.

Leuchars operated Lightnings until around 1969.

F4 Phantoms followed for the next several decades with Tornados only becoming operational from that Airfield in April 2001.

Since you mention the lake (loch) you must have been flying from the Scottish Gliding Union at Portmoak - I am left wondering who the instructor was as I must admit to never having heard of this incident. Perhaps you could PM me with the name as I do have an interest as a past CFI and safety officer at Portmoak.

It is possible that the aircraft were indeed Phantoms as the Americans also operated this type within the UK and were, quite often, involved in the low flying and other military operations with the Scottish region.

The usual route to/from Leuchars was to the North of Bishop Hill between that and the Ochils. Americans, unfamiliar with the area, might well have aimed for the gap between Bishop and Benarty Hills although that track would also have taken them low over Glenrothes airfield to the East of Portmoak.

Leuchars were well aware of Portmoak and there was a letter of agreement between them and the Scottish Gliding Union re their circuit requirements in Easterly winds as they came close to our own circuit in those conditions.

A somewhat out of context post but I am intrigued by your experience.

As an aside low slow or steep turns in gliders close to the ground, especially long span ones, were never a good idea. This was not so much because of the danger of the lower wing stalling from being in the lower slow moving mass of air on turning into wind but more from the differential lift between the tips at differing airspeeds. The lower wing in slower wind speed due to wind gradient effect plus moving at lower speed than the outer wing equals a considerable amount of extra lift on the upper wing. The early long span gliders were a bit lacking in aileron effectiveness and thus might not have had powerful enough ailerons to actually level the wings for landing.
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Old 4th Feb 2017, 19:41
  #120 (permalink)  
 
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My last dual flight before solo in a K13, Lasham, 1990 - instructor pulled off the winch launch early, 900 feet, but told me to keep the nose up into a stall, then bank to the left, which precipitated a spin - normal spin recovery, lost 400 feet with just over 1 revolution, so about 600 feet when recovered, just right for a normal circuit. He cleared me to solo after that.

FBW
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