If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
Initial acceleration is certainly much slower with autotow (whether
pulley or direct) than with winching. At both North Weald and Aston Down there was more than one runway, so most launches were broadly into-wind. Such cross wind as there was could be handled. The initial ground run was a phase of flight in its own right - the pilot had to learn to balance on the wheel and taxi straight until flying speed was achieved. Wingdrop was not normally a problem, but training people to taxi was a feature. The same considerations apply when landing, in any case, so they got two lots of taxi training in one flight. On tarmac or concrete the F250 trucks had adequate power and grip. F100' s were not bad, but we didn't have such heavy gliders in those days. Aston Down tried a variety of tow vehicles over the years, including some home-built diesel dragsters, but I believe they ended up with factory-built trucks, as we did, and as Lasham (using straight autotow at one time) also did. I worked for Ford then, and helped to get some advantageous prices for imported US-built vehicles for two if not all three clubs IIRC - Ford used gliders at North Weald as background for some advertisements, and did us a favour in return. My club used LPG rather than petrol/gasoline, which made it a comparable fuel cost to diesel winching, per launch/cable-retrieve. Total depreciation/financing cost was probably about comparable, but needed less cash flow up front. Trucks were cheaper capital cost than new winches, though not as durable - ours lasted for about 50,000 launches each and were not fully worn out - we recycled one old powertrain into a winch when we had to adopt that method for our Ridgewell site. The key features for us at North Weald were that on hard runways we had to use piano wire (single strand steel cable), not stranded, to avoid too much wear and cable cost, and pulley/autotow lends itself to that better, with pulley giving also the benefit of fast launch rate when well organised. We did about 9,000 launches a year, and added considerably to our cash flow, when we had optimised the system. Chris N. |
#12
|
|||
|
|||
The initial acceleration for a car or reverse pulley launch is no worse than
for an aerotow; it is flown in the same way. There is of course no tug slipstream to contend with. A car launch starts like an aerotow, and turns into a winch launch when you are airborne. W.J. (Bill) Dean (U.K.). Remove "ic" to reply. "Chris Nicholas" wrote in message ... Initial acceleration is certainly much slower with autotow (whether pulley or direct) than with winching. At both North Weald and Aston Down there was more than one runway, so most launches were broadly into-wind. Such cross wind as there was could be handled. The initial ground run was a phase of flight in its own right - the pilot had to learn to balance on the wheel and taxi straight until flying speed was achieved. Wingdrop was not normally a problem, but training people to taxi was a feature. The same considerations apply when landing, in any case, so they got two lots of taxi training in one flight. On tarmac or concrete the F250 trucks had adequate power and grip. F100's were not bad, but we didn't have such heavy gliders in those days. Aston Down tried a variety of tow vehicles over the years, including some home-built diesel dragsters, but I believe they ended up with factory-built trucks, as we did, and as Lasham (using straight autotow at one time) also did. I worked for Ford then, and helped to get some advantageous prices for imported US-built vehicles for two if not all three clubs IIRC - Ford used gliders at North Weald as background for some advertisements, and did us a favour in return. My club used LPG rather than petrol/gasoline, which made it a comparable fuel cost to diesel winching, per launch/cable-retrieve. Total depreciation/financing cost was probably about comparable, but needed less cash flow up front. Trucks were cheaper capital cost than new winches, though not as durable - ours lasted for about 50,000 launches each and were not fully worn out - we recycled one old powertrain into a winch when we had to adopt that method for our Ridgewell site. The key features for us at North Weald were that on hard runways we had to use piano wire (single strand steel cable), not stranded, to avoid too much wear and cable cost, and pulley/autotow lends itself to that better, with pulley giving also the benefit of fast launch rate when well organised. We did about 9,000 launches a year, and added considerably to our cash flow, when we had optimised the system. Chris N. |
#13
|
|||
|
|||
Ridgewell, that's the place old Fred had the steam winch. Of course, he was
shunned by most BGA types. There's still a story out there somewhere. Maybe someone will ask around this winter. Frank Whiteley |
#14
|
|||
|
|||
Frank Whiteley wrote: "Ridgewell, that's the place old Fred had the
steam winch. Of course, he was shunned by most BGA types. There's still a story out there somewhere. Maybe someone will ask around this winter." It was diesel, not steam, but made from a converted combine harvester. The saga of Freddie's club is fairly complicated, but he was far more tolerated by the BGA and quite a lot of BGA types until he made it impossible to be allowed to carry on in BGA membership. His achievements in starting a club from scratch, converting a rough field at Ridgewell into a useable gliding site, backing it with his own money, and carrying on until illness intervened, were prodigious. We all recognized those things, and perhaps let him get away with other foibles for too long. My club has since benefited from his pioneering efforts, having bought the site in 1991 when it looked like we would lose the use of North Weald. Before starting his own club, Freddie acquired a PPL and a Silver C elsewhere. He went on an instructors course, and failed to qualify. When his own club had mustered the enough equipment to start, he appointed himself Chief Flying Instructor (CFI). In establishing the club, he sought help from, and was given it by, the BGA, free gratis. He did not join straight away, but did after a while. The BGA tolerated his lack of qualifications and tried to get him up to standard, but he was unable to reach the level needed. The BGA tried to get him to accept a qualified instructor from elsewhere as CFI, but he refused. He then claimed to be operating in two ways. When there was no BGA-qualified instructor on the site, he said he had a soaring group and he was carrying passengers and letting them try the controls. When his passengers had reached solo standard as he thought, he then called in a visiting instructor from elsewhere, called it a gliding club that day, and got the visitor to check out his students so they could have a BGA A and B certificate. The BGA let this go on for some years, all the time trying to get him either up to scratch himself or persuade him to accept outside help. I was on the BGA Executive Committee at the time, and took an active part in trying to help - to no avail. During this time, there were various events which brought interest from outside authorities. One was a tug accident, Fred towing and IIRC hitting his own mechanical shovel. After one of these, he was again assessed by the BGA, and a second opinion sought when he refused to accept the first. Both thought he was not up to instructing. There were also concerns about the airworthiness of his fleet. Eventually the BGA delivered an ultimatum. He was in breach of a prime regulation - not having a CFI with qualifications, and himself instructing while unqualified. I went personally to try to persuade him to accept another CFI, and at one time I thought I had succeeded. But he then dug in and refused to accept it. The BGA put it to a General meeting and it was resolved, with only his vote against, to discontinue his club's BGA membership. What would any responsible regulatory body do? Sadly, he fell ill and died not long after. His club went moribund. After his death, several of my friends and colleagues helped to set up his club again. My club's deputy CFI went to help, and promptly declared all their gliders unserviceable through neglect. Eight of us bought them a K7 2-seater to start again. (I have just sold it for virtually nothing, so lost 1000 sterling on it.) One of my friends became their CFI and technical officer. I persuaded the BGA to let them back in without paying a subscription for a year. Then they lost the use of their site, and went into hibernation again until we bought it a few years later. Several of their members joined us - several more were members of both clubs anyway, having helped in their regeneration. I think Freddie's family held me personally responsible for the rift, when in fact I had done all I could, and more than most, to try to help. I could say more, but that covers the essential part of a strange story. Somebody else can write up the saga of the combine harvester winches (I think there were two in succession). Chris N. |
#15
|
|||
|
|||
"Chris Nicholas" |Hi Chris, Remember me? I was an instructor at North Weald from 1972 till 1978 when I went to the LGC (a bad move) and gave up gliding when they refused to ratify my instructor's ticket (I only had 1000 launches instructing and about 20 solo pilots to my credit). However the winch story is interesting. When I was at the Staffordshire Club in the late 60s I designed(!!) and built a diesel winch which consisted of two old artic tractors , one mounted on the top of the other (looked like a particularly nasty copulation). The lower lorry was for transport and the upper had its wheels replaced by large drums with brakes. You braked one drum and the other ran at twice prop shaft speed using the diff as a gear (didn't half heat up the oil). Worked a treat and was very economical. I never saw anyone else try this method. The SGC called it the 'Winchosaurus' as it certainly looked primeval! Alistair Wright long retired glider pilot |
#16
|
|||
|
|||
Chris,
Thank you very much. That fills in a lot of details. For sure, our club CFI and Chairman told us to steer well clear. Frank Whiteley "Chris Nicholas" wrote in message ... Frank Whiteley wrote: "Ridgewell, that's the place old Fred had the steam winch. Of course, he was shunned by most BGA types. There's still a story out there somewhere. Maybe someone will ask around this winter." It was diesel, not steam, but made from a converted combine harvester. The saga of Freddie's club is fairly complicated, but he was far more tolerated by the BGA and quite a lot of BGA types until he made it impossible to be allowed to carry on in BGA membership. His achievements in starting a club from scratch, converting a rough field at Ridgewell into a useable gliding site, backing it with his own money, and carrying on until illness intervened, were prodigious. We all recognized those things, and perhaps let him get away with other foibles for too long. My club has since benefited from his pioneering efforts, having bought the site in 1991 when it looked like we would lose the use of North Weald. Before starting his own club, Freddie acquired a PPL and a Silver C elsewhere. He went on an instructors course, and failed to qualify. When his own club had mustered the enough equipment to start, he appointed himself Chief Flying Instructor (CFI). In establishing the club, he sought help from, and was given it by, the BGA, free gratis. He did not join straight away, but did after a while. The BGA tolerated his lack of qualifications and tried to get him up to standard, but he was unable to reach the level needed. The BGA tried to get him to accept a qualified instructor from elsewhere as CFI, but he refused. He then claimed to be operating in two ways. When there was no BGA-qualified instructor on the site, he said he had a soaring group and he was carrying passengers and letting them try the controls. When his passengers had reached solo standard as he thought, he then called in a visiting instructor from elsewhere, called it a gliding club that day, and got the visitor to check out his students so they could have a BGA A and B certificate. The BGA let this go on for some years, all the time trying to get him either up to scratch himself or persuade him to accept outside help. I was on the BGA Executive Committee at the time, and took an active part in trying to help - to no avail. During this time, there were various events which brought interest from outside authorities. One was a tug accident, Fred towing and IIRC hitting his own mechanical shovel. After one of these, he was again assessed by the BGA, and a second opinion sought when he refused to accept the first. Both thought he was not up to instructing. There were also concerns about the airworthiness of his fleet. Eventually the BGA delivered an ultimatum. He was in breach of a prime regulation - not having a CFI with qualifications, and himself instructing while unqualified. I went personally to try to persuade him to accept another CFI, and at one time I thought I had succeeded. But he then dug in and refused to accept it. The BGA put it to a General meeting and it was resolved, with only his vote against, to discontinue his club's BGA membership. What would any responsible regulatory body do? Sadly, he fell ill and died not long after. His club went moribund. After his death, several of my friends and colleagues helped to set up his club again. My club's deputy CFI went to help, and promptly declared all their gliders unserviceable through neglect. Eight of us bought them a K7 2-seater to start again. (I have just sold it for virtually nothing, so lost 1000 sterling on it.) One of my friends became their CFI and technical officer. I persuaded the BGA to let them back in without paying a subscription for a year. Then they lost the use of their site, and went into hibernation again until we bought it a few years later. Several of their members joined us - several more were members of both clubs anyway, having helped in their regeneration. I think Freddie's family held me personally responsible for the rift, when in fact I had done all I could, and more than most, to try to help. I could say more, but that covers the essential part of a strange story. Somebody else can write up the saga of the combine harvester winches (I think there were two in succession). Chris N. |
#17
|
|||
|
|||
Alistair, Hi! I certainly remember you. Didn't know where you went
after North Weald. I have seen a recent posting which suggested that using the diff as the drive for a winch drum on the axle and doubling the speed is not a recipe for long life. As others have pointed out, a better long term solution seems to be a proper rightangle drive (the crown wheel and pinion seem fine for that) and dog clutches for the drum, one at a time and at crown wheel speed. I did not see your winchosaurus, but I believe that there have been an amazing variety of winches over the years. The most eccentric I know of were Freddie Wiseman's 1977 converted combine harvester at one end of the scale, and a totally portable, demountable, device to bolt onto the hub of a Rover car at the other extreme. The latter was a commercial offering, again in the 1970's. When we lost the use of wire launching at North Weald but had bought Ridgewell and needed to acquire one or more winches, we tried a converted bus. That had two axles, one above the other, rather than the whole second chassis. It had one drive shaft which had to be disconnected from the lower axle after driving the bus to the winch point, and reconnecting it to the higher, drum, axle. IIRC it had dog clutches. We didn't buy it because it was unreasonable expensive and looked as though it was not a sufficiently long term solution for us. I had seen a similar arrangement in 1970 when Essex's original winch was an old truck with that idea. I had my first instructional launch from it, one cold March morning when there was too much ice to autotow. Got 300 feet and a free second go, which was not much better. Now, we have ended up with 4 ex-ATC winches bought at auction, getting two reasonable ones from them plus a lot of spares, and replacing their powertrains. One had a total cab transplant too, professionally built; the other is in the course of having a lower cost replacement cab, made by some of our members. Regards - Chris. |
#18
|
|||
|
|||
"Chris Nicholas" wrote in message ... Alistair, Hi! I certainly remember you. Didn't know where you went after North Weald. I have seen a recent posting which suggested that using the diff as the drive for a winch drum on the axle and doubling the speed is not a recipe for long life Quite true as we found out. We had a source of free lorry back axles at the time and we went through a fair number till we altered the lubricating system to thinner oil with a pump and cooler. I left SGC about that time so have no data on the subsequent fate of that winch. Considering it replaced our original S/H ex Derby and Lancs one (Ford V8) which was on its last legs when we bought it , it did pretty well. My next club was the Coventry GC at Husbands Bosworth where very little winching took place -- I only had about 4 in as many years - it was all aero-towing at HB. I did not see your winchosaurus, You were lucky then! It wasn't a pretty sight I can tell you. I have a model of it somewhere. When we lost the use of wire launching at North Weald but had bought Ridgewell and needed to acquire one or more winches, we tried a converted bus. I used to think NW's auto towing was magic. On a good day you could get twenty launches an hour. Didn't half use up Ford Zephyrs though!! Now, we have ended up with 4 ex-ATC winches bought at auction, getting two reasonable ones from them plus a lot of spares, and replacing their powertrains. One had a total cab transplant too, professionally built; the other is in the course of having a lower cost replacement cab, made by some of our members. Good idea. The ATC jobs were very well built and designed to launch T21s. A winch that could hoist one of those to 1000ft would launch anything. Best wishes Alistair All the best to any others in the EGC who remember me. |
#19
|
|||
|
|||
"Alistair Wright" wrote in message ... "Chris Nicholas" wrote in message ... Alistair, Hi! I certainly remember you. Didn't know where you went after North Weald. I have seen a recent posting which suggested that using the diff as the drive for a winch drum on the axle and doubling the speed is not a recipe for long life Quite true as we found out. We had a source of free lorry back axles at the time and we went through a fair number till we altered the lubricating system to thinner oil with a pump and cooler. I left SGC about that time so have no data on the subsequent fate of that winch. Considering it replaced our original S/H ex Derby and Lancs one (Ford V8) which was on its last legs when we bought it , it did pretty well. My next club was the Coventry GC at Husbands Bosworth where very little winching took place -- I only had about 4 in as many years - it was all aero-towing at HB. I did not see your winchosaurus, You were lucky then! It wasn't a pretty sight I can tell you. I have a model of it somewhere. When we lost the use of wire launching at North Weald but had bought Ridgewell and needed to acquire one or more winches, we tried a converted bus. I used to think NW's auto towing was magic. On a good day you could get twenty launches an hour. Didn't half use up Ford Zephyrs though!! Now, we have ended up with 4 ex-ATC winches bought at auction, getting two reasonable ones from them plus a lot of spares, and replacing their powertrains. One had a total cab transplant too, professionally built; the other is in the course of having a lower cost replacement cab, made by some of our members. Good idea. The ATC jobs were very well built and designed to launch T21s. A winch that could hoist one of those to 1000ft would launch anything. When we re-engined an ATC winch at Enstone from 150hp Bedford diesel to the 275hp XJ-6 Jag we got some pretty solid launches. After a time we developed a vibration and thought one of the pillow blocks on the drum had given up, but this wasn't the case. The vibration got worse, so we pulled all of the wire from the drum and found it to be collapsing inward under the strain of launching the Twin Astir and L-13 under more power than the winch had been designed for. Frank Whiteley |
#20
|
|||
|
|||
Frank Whiteley wrote [snip] " we pulled all of the
wire from the drum and found it to be collapsing inward under the strain of launching the Twin Astir and L-13 under more power than the winch had been designed for." This happened to another club, and I am concerned it might to us too. What did you do do to fix it - could the ATC-type drum be suitably reinforced to prevent it, or did it need a new drum which would no doubt be of heavier material or with added stiffeners inside? Chris N. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
vortex ring state at any point during an auto?? | Greg Johnson | Rotorcraft | 18 | August 30th 04 09:12 PM |
Auto Fuel Residue | Stu Gotts | Restoration | 4 | May 12th 04 08:52 PM |
Auto conversions & gear boxes | Dave Covert | Home Built | 56 | April 1st 04 06:19 PM |
Arrow auto gear extension oddness | Roy Smith | Owning | 10 | March 8th 04 02:27 AM |
VOR & Reverse Sensing | mrwallace | Piloting | 1 | August 21st 03 03:08 AM |