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Gliding - now I get it

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Gliding - now I get it

Old 12th Nov 2020, 20:50
  #61 (permalink)  
 
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Originally Posted by VP959 View Post

Does anywhere still do auto tow launches? We had a couple of old Rover 3.5 litre automatics, converted with a hook mounted on the roof, together with a hole cut out of the roof to access the hook. There was a deal at the club where if you agreed to drive the tow car for half a day you could get either an aero tow or three auto tow launches for free, so being skint I seemed to spend a lot of time driving these battered old Rovers.
Connel used to do auto launches behind an elderly middle-aged V12 Jaguar. I was supposed to get qualified (if that's that right word) with it, but a 3 day tail-end of hurricane put an end to that. High point of the otherwise washed-out week was getting into the wave off Mull on the last day. But we launched with no oxygen or even cameras
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Old 12th Nov 2020, 21:37
  #62 (permalink)  
 
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At Lasham in the late 1950's, and maybe well after that, we used to run two winches and a car tow using a battered American pickup with an automatic shift. The winches were on either side of the runway. The car cable was single strand, ie stiff, wire (Why?..... dunno) and very prone to kinking and breaking if the car driver wasn't careful; after the glider released you had to speed up as the cable fell, to lay it out straight, then get the other end and pull it back to the launch point. On a good wind day you could play the glider like a kite to get a bit more height, slowing to maybe 20-30 mph, but if the release was too late there wasn't much runway left to lay the cable out.......driving the tow car was almost as much fun for an 18 yr old as the flying.

Dan Air maintained their Yorks at Lasham then, so every now and again we had to clear the runway as a York trundled into view at 500 ft, wheels down, belching exhaust smoke, often on 3. At different times one would appear from behind the hangars, taxying to take off, and we again have to clear away. The first attempt was often unsuccessful, but after adjustments and a ground run it would eventually heave itself into the air and disappear, still smoking heavily.
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Old 12th Nov 2020, 21:43
  #63 (permalink)  
 
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The tow cable we used was parafil, a hard black plastic sheath containing a bundle of very fine fibres, of kevlar, I think. It was better than wire in terms of not being prone to kinking, but it used to get damaged if dragged back along the hard runways, so we'd tow it back on the grass alongside. Expensive stuff I was told, usually after being accused of having scraped it on the runway . . .
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Old 12th Nov 2020, 22:58
  #64 (permalink)  
 
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Originally Posted by old,not bold View Post
The car cable was single strand, ie stiff, wire (Why?..... dunno) and very prone to kinking and breaking if the car driver wasn't careful
Stranded Wire Cable cannot cope with rough surfaces,before the advent of Parafil etc,single strand wire was used.
In Zimbabwe we used Fencing Wire on the winch at Midlands Gliding Club,Moffat Field for the same reason - ie because the ground and broken up runways were extremely rough - and of course fencing wire was extremely prone to kinks and breaks LOL
We did not have the option of towing cables on the grass.
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Old 13th Nov 2020, 09:03
  #65 (permalink)  
 
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Originally Posted by Krystal n chips View Post
OK, well it would be fair to say I think I am more than familiar with the difference between an aerotow and a winch launch, albeit all the checks such as GH / steep turns, / spins / stalls can easily be achieved off a winch launch. ......
LOL Krystal n chips! You may be - but some maybe not so - so my humble apologies if I sounded patronising - not my intent! Now, in my defence, re doing all the above off a Winch, well, it sort of depends on the conditions ususally found at Base!!

Where we used to do this was a UK coastal site, blessed either with UK Winter (Winter) or permenant Sea Breeze (Summer), the latter which killed everything dead until you got several miles inland. Getting away off from there on a winch was an absolute miracle! My log book, when flying there, is 80% "4 minute wonders" - the rest aero-tows!! Virtually the only time I (or anyone!) got away off the winch was on a (very) small handfull of occasions - hence aero-tows were widely used - but ......... we usually only had 1 tug.

So winch was at least a way to get people into the air - even if not for long. Standard on the winch (99.99999% of the time) it was up to 1k and then 3 to 4 minutes back to "wheels-on" at the launch point!!!! If you were really, really, really lucky, you might get a couple of turns in between top of launch and High Key otherwise the Vario would suggest the following routing:- TOC - DCT - HKP - DCT - LKP - DCT - FIN - DCT - LND!

I agree, at other sites I visited it was different - but at my main base for several years we were less fortunate! Anyway, just my 1/2p-worth!!! And it was still BRILLIANT fun!!!!!!!

Like the time a patronising Admiral came up and lectured me and my mate (we were in the middle of our start-of-day winch cable check run-out duties) on taking care doing our checks. My mates reply "Certainly Sir, but as we are driving the winch today too, we'll be leaving a few of the more dodgy joins in so we can have some fun!" before dropping the clutch on the tractor and leaving the poor VSO speechless in our wake was priceless!!!! I nearly died laughing!!!!! To be fair, said Admiral found us at the end of the day and thanked us for our stirling service on the winch that day .... but I have always blamed that day on why I got no-where in the Services!!!
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Old 13th Nov 2020, 10:11
  #66 (permalink)  
 
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Originally Posted by VP959 View Post
Does anywhere still do auto tow launches?
The RAE Gliding Club at Farnborough used auto tow until they got fed up with having to move off the runway for a bizjet movement (mid/late '90s) and decided to move to Odiham where they operated alongside the winch launched RAF and Army gliding clubs. Within a few months they were asking to come back !
I have heard of a 'reverse tow' system whereby the cable goes round a pulley at the upwind end of the runway and the tow car drives towards the launch point, thus the 'problem' of returning the end of the cable to the launch point doesn't happen.
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Old 13th Nov 2020, 18:22
  #67 (permalink)  

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I have heard of a 'reverse tow' system whereby the cable goes round a pulley at the upwind end of the runway and the tow car drives towards the launch point, thus the 'problem' of returning the end of the cable to the launch point doesn't happen.
I am clearly missing something here but whichever end the cable ends up after a launch it has to be towed back to the launch point does it not?

I have done some gliding on and off and really enjoyed winch driving. Out of curiosity I started looking at types of winch cable last night and found a company called Skylaunch who build and repair winches. They seem to really know their subject but I came across a system I have never seen before where the launch cable also has a 'retrieve' cable attached to a small winch at the launch area. As the glider ascends and the winch cable is wound in the retrieve cable is pulled out from the small winch. After launch the small winch winches in the retrieve cable and pulls the launch cable back to the launch area. It all seems very clever and massively reduces time spent towing the cable back to the launch area.

Skylaunch website
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Old 13th Nov 2020, 19:45
  #68 (permalink)  
 
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The reverse tow is an auto tow system, with launches alternating from each end of the cable. It usually stays wrapped around the end pulley, all that happens is that the car tows its end of the cable back to the launch point, after the glider has released, then it releases the cable ready for that end to be attached to the next glider. The car then drives back along the runway to pick up the end dropped by the glider, hooking that on, ready for the next launch. The cable usually ends up only needing to be dragged maybe half the distance or less, so it's potentially quicker, albeit with a risk posed by the oncoming car if the cable breaks during the launch.
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Old 13th Nov 2020, 20:30
  #69 (permalink)  
 
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Originally Posted by M.Mouse View Post
They seem to really know their subject but I came across a system I have never seen before where the launch cable also has a 'retrieve' cable attached to a small winch at the launch area. As the glider ascends and the winch cable is wound in the retrieve cable is pulled out from the small winch. After launch the small winch winches in the retrieve cable and pulls the launch cable back to the launch area. It all seems very clever and massively reduces time spent towing the cable back to the launch area.

Skylaunch website
We trialled a retrieve winch at Halton in Winter 1970/71,we were evaluating the launch rate achievable/safety of etc,of necessity it was single cable operation but it did cut right down on vehicle damage to the Airfield (grass).It was a fairly noisy little beast,one of the guys built a silencer for it out of cardboard boxes which kept us warm when it caught fire .Fairly straightforward to use as long as the 'triangle' to attach the retrieve cable to the main cable was laid out correctly.It is a very useful system for gliding sites with either extreme terrain or boggy terrain in parts of the operating field.
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Old 13th Nov 2020, 20:39
  #70 (permalink)  
 
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Ulster and dublin Kerry safari

The two clubs have an annual joint safari in September..launch off the beach..height records around 23,000ft.
Not getting involved in the winching debate but will say I was instrumental in "forcing" the BGA to change their procedures around 14 years ago which brought down the ten year fatality rate by 50%. Far too many pilots did not understand the dangers which included instructors.

Auto towing from inch strand Dingle

K8 near Connor pass after auto tow off Fermoyle
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Old 14th Nov 2020, 05:22
  #71 (permalink)  
 
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Originally Posted by treadigraph View Post
I found I had became quite sensitive to neg G in light aircraft when I got a bit older, maybe after 40, not sure why but anything that had my bum going light on the seat and also steep turns made me a bit uncomfortable. Flying has been too infrequent for me to assess whether I would get used to it again!
Life's odd like that - I felt that way when I was younger, but now I welcome slight discomfort or abnormal weight sensations in the air. Maybe I just need those feelings to confirm that I am still alive. 😊
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Old 14th Nov 2020, 17:17
  #72 (permalink)  
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hot n high ....sorry about the delay in replying. Not in the least offended, if I was, I would happily reciprocate .....anyway, you mentioned sea breeze fronts and Admirals, which sort of narrows down your possible locations doesn't it.

Never met the species to be honest, only those lower down the food chain, but did meet quite a few of the RAF / Army equivalent. Only encountered a sea breeze at the, sadly short lived, probably because the key requirement, the bar !!, was missing, club at St Mawgan

Back to the operational aspects you described. As I said, I'd never encountered this format, so, I asked some friends in the GSA and lo and behold, it wasn't unknown to them. However, what they did say, was, whilst having altitude available was obviously useful for Bloggs, and anybody else who may have needed it, when it came to the simulated "twang ! " this was always done on the wire. So that's that sorted.
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Old 14th Nov 2020, 18:12
  #73 (permalink)  
 
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Talking of the BGA, is a former RAE colleague of mine, Howard Torode, still involved with them? I remember him inviting me to a BGA meeting at Lasham years ago, at the time when the BGA were working out what they needed to do to get gliders to comply with the new airworthiness and registration requirements that were being imposed. I remember much tearing out of hair by some of the BGA luminaries present. The prevalent view seemed to be that there was no need to change a system that was safe and well understood by all.
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Old 15th Nov 2020, 16:25
  #74 (permalink)  
 
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Originally Posted by Krystal n chips View Post
..... Back to the operational aspects you described. As I said, I'd never encountered this format, so, I asked some friends in the GSA and lo and behold, it wasn't unknown to them. However, what they did say, was, whilst having altitude available was obviously useful for Bloggs, and anybody else who may have needed it, when it came to the simulated "twang ! " this was always done on the wire. So that's that sorted.
Indeed K 'n C, and, what's that old saying? "If in doubt get the log-books out!!" ((c) H 'n' H, 2020)

Just checked and I do have duals of 40-ish mins followed by c. 4min followed by c. 2min on the same day/same a/c so, clearly, we "practiced" at altitude on aero-tows and "checked" off the wire which, as you and others say, makes complete sense!!! Not flown a winch for a considerable period - hence clearly forgotten that - and actually quite a gap since last in a glider (where do the years go???). Also, I enjoyed the challenge of cable-breaks - which is maybe why I forgot that part as it was "normal"!

That said, I was always pleased to be off the wire at TOC or after a cable break. While fun to fly, I also saw one incident early on where we almost lost 2 people on a winch launch. Thankfully the crew sorted it somehow, but it led to an erie stunned silence at the launch point as it rapidly unfolded before our eyes (and some expletives at the winch I'd wager). Best thing tho; it showed me just how quickly a winch launch could go seriously pear-shaped if mis-handled in any way! Thankfully, just a change of underwear required by the crew involved - but it was really close!

And all my cable break practice was taken fwd into Commercial flying when I had STOL take-offs to do - never had to use it but I always briefed a "cable break" type recovery had we lost an engine on a steep climb-out (single or multi). Thankfully, they remained just "briefs"!!!! Anyway, enough of me and cable breaks!! Back under me stone before I bore everyone rigid!

What do you mean "Too late, Mate!"???!!!
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Old 15th Dec 2020, 11:55
  #75 (permalink)  
 
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Reverse Pulley Autotows

Please excuse me for butting in

When I flew at Aston Down in the mid 90s we had a reverse pulley launch system: It basically involved Ford F150 6.4L(?) pick ups running on propane, piano wire and a very large wheel contraption attached to the back of a Bedford truck. The wheel could rotate vertically as well as allowing the cable to run through it. The cable itself was double ended and attached to a frame in the pick up bed with a Tost quick release fitted. The other end was obviously attached to the glider. The launch was with the usual light signals. There was a strain gauge in the cab whereby you could judge the optimum speed, but actually the MK1 eyeball proved as accurate but meant driving forwards at speed whilst looking back and upwards
You drove an S curve up the runway, initially heading up the upwind side(giving space for the glider if it all went twang), then down the middle as the glider gained height and then back to the side of the runway at the launch point.
It all worked well, but launching an ASH-25 on a flat calm hot day meant things could get 'interesting' if you weren't on the ball...
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Old 15th Dec 2020, 12:15
  #76 (permalink)  
 
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As there appear to be a few ex (V)GS types on here, this thread might be of interest too...Air Cadet Gliding pix in the 80s (pre glass)
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Old 15th Dec 2020, 14:20
  #77 (permalink)  
 
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Here are some pics of our set-up at Aston Down...Reverse Pulley Ground Launch System
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Old 15th Dec 2020, 15:36
  #78 (permalink)  

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My Intro to flying was at RAF Swanton Morley after I was lucky enough to be allowed a CCF sponsored weeks course to solo standard. All from the winch. My third flight was the first time Id ever touched the controls and to my terror, the instructor in the rear seat (also the CGI, Ron Paige) yelled me through the final turn. I was obviously expecting him to take control for the landing but he didnt! I managed to land well enough but as we slowed on the ground he yelled at me to pick the wing up with rudder. As I hadnt been briefed on how to do this I thought Id better choose which foot! I got it wrong, the wingtip hit quite hard and we did a partial ground loop. The yelling continued! At the end of the debrief I explained that it was my first ever attempt to fly anything. He went very quiet...I believe hed got me confused with a far more experienced student and I later received a partial apology.

Later in the week I was approaching first solo. I flew with F/O Silver. During the winch launch I realised we were flying quite a lot faster than we should have been. I wagged the tail as the signal to the winch driver to slow it down but it seemed to make no difference. I became so concerned that we were exceeding the max IAS that I shoved the nose down and pulled the cable release. I S turned us back to a safe landing near the winch and to my surprise received my second rollicking of the week! I thought what I did was perfectly justified so I remember feeling quite put out. I went solo the next morning!
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Old 15th Dec 2020, 16:47
  #79 (permalink)  
 
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My first solo in a glider was memorable. I was on the second of a set of three auto tows, when I ended up in a bit of sink on finals, and was way too low. The yell from next to me was "what are you going to do about it?", followed quickly by an instruction to get the nose down, pull the brakes back in, punch through the sink, then use the speed to make it to the piano keys (just). I used to smoke back then, so asked if I could sit and have a cigarette before the last of that set of three launches. The instructor climbed out, whilst I sat there, canopy open, trying to calm down a bit. When he returned, he proceeded to fit ballast weights where his seat was, and when I asked what he was doing, he just said "You don't think I'm bloody flying with you again, do you? You're on your own". What should have been exhilaration at my first ever solo in anything was anything but. All I can remember is concentrating like mad on trying to fly as well as I possibly could, and get the thing back on the ground in one piece. Thankfully, the club had a policy of no more flights the same day following a first solo, so I had time to recover, before my wallet got somewhat battered in the bar that evening.
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Old 15th Dec 2020, 17:56
  #80 (permalink)  
 
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At Locking, we used to launch behind the "horse" part of an old articulated truck with a crash box. Considering that one had to move through five gears to finally achieve around 45-50 mph, one's left leg developed a serious case of the shakes after doing it for an hour or two.

At least the winch had a lever assist on the clutch which eased the anguish. On occasion one was requested to "kite him up", when the wind was right. However, some time later he got up to well over 2000', and, after half a mile of cable had dropped on the roof of the winch, I declined future requests.

All good fun, but completely off limits these days I imagine.

I remember the day when a narly instructor could be heard shouting at his student...."DO NOT TRY TO SIDE SLIP MY GLIDER DURING THE FLARE" as they passed the bus at speed and landing long.

IG
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