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#21
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On Thu, 24 Jul 2003 17:05:30 +1000, Geoff Vincent
wrote: FWIW, My experience airotowing using a belly hook has been limited to my PIK 20B, fitted with Mazak winglets, using the Aussie low-tow technique. Take-off procedure is stock standard: 1. Select full negative flap (-8 deg) 2. Select full forward trim 3. Hold the ship on the ground with back stick until full aileron control established. 4. Ease stick forward and ease flaps to neutral. Ship lifts off with no further elevator input. 5. Hold ship at 5-10 feet until tug lifts off and rises above glider. 6. Glider follows just under tug slip-stream. ( If there is a cross wind hold the ship on ground longer until just before tug lifts off). The above gives excellent directional control on the ground with no tendency to drop a wing or drift off-line. Ropes are standard 55 metres length. In the air (low tow position) directional stability is excellent but one needs to read changes to the tug's angle of bank quickly. Only had one (short-term) scare when, in my first competition, the tug went into a 45 degree RH bank into a thermal at 600'. Took a few milliseconds to regain my equilibrium!! Only had one other experience of concern when an experienced tuggie persuaded me to undertake an outlanding retrieve (from a remote airfield) using a 35 meter rope - an experience I didn't enjoy and wouldn't recommend. Overall, aerotowing with the belly hook hasn't presented any difficulties worth worrying about and well-intentioned (doom and gloom) predictions by instructors and winch drivers fortunately have proved groundless. Geoff Vincent Mangalore Gliding Club Australia VH-GAX Right on Geoff, I hate short ropes. Most of the problems with belly hooks and aerotow go away if you use a decent length of rope. 55 meters is a little too short though. About 240 feet is about right. One of the nearby clubs started doing this and after some time, one day one of the old shorter ropes came out and was used. After a couple of tows the tugpilot went back to the hangar to get the long rope. He could tell how much easier the glider pilots found the long rope. Mike Borgelt |
#22
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I have experience of two different kinds aerotowing from a CG hook:
1. Launching an LS4 (tailskid) from an unmade (dirt, gravel, rocks) runway. The problem here was directional control, with the glider snaking around until there was enough speed for the rudder to counter the crosswind. Not a real problem but hard work for 2 or 3 seconds. Hand on release in case the direction of tug and glider get too far apart. 2. Launching my Open Cirrus (tailwheel) from a paved runway. Absolutely no directional control problems at all. By the time the tailwheel is lifting, the rudder is working. Just be aware of the possibility of swinging once the tail comes up - whether there's any swing will probably vary between glider types, but I've never noticed anything with the Cirrus. There is, for all CG hook aerotows, the danger that if the glider gets high it will begin to winch launch itself. I'm told this will pull the tug tail up and cause more excitement than anyone wants (or worse than excitement if low down). Neither the LS4 nor the Cirrus showed any signs of doing so, but I kept a watch on the tug position ready to release if it got away from me. |
#23
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On Thu, 24 Jul 2003 13:02:00 +0100, "Chris Reed"
wrote: I have experience of two different kinds aerotowing from a CG hook: 1. Launching an LS4 (tailskid) from an unmade (dirt, gravel, rocks) runway. The problem here was directional control, with the glider snaking around until there was enough speed for the rudder to counter the crosswind. Not a real problem but hard work for 2 or 3 seconds. Hand on release in case the direction of tug and glider get too far apart. 2. Launching my Open Cirrus (tailwheel) from a paved runway. Absolutely no directional control problems at all. By the time the tailwheel is lifting, the rudder is working. Just be aware of the possibility of swinging once the tail comes up - whether there's any swing will probably vary between glider types, but I've never noticed anything with the Cirrus. There is, for all CG hook aerotows, the danger that if the glider gets high it will begin to winch launch itself. I'm told this will pull the tug tail up and cause more excitement than anyone wants (or worse than excitement if low down). Neither the LS4 nor the Cirrus showed any signs of doing so, but I kept a watch on the tug position ready to release if it got away from me. Sounds like excellent justification to fly low tow. Geoff Vincent Australia |
#24
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"Chris Reed" wrote
I have experience of two different kinds aerotowing from a CG hook: 1. Launching an LS4 (tailskid) from an unmade (dirt, gravel, rocks) runway. The problem here was directional control, with the glider snaking around until there was enough speed for the rudder to counter the crosswind. Not a real problem but hard work for 2 or 3 seconds. Hand on release in case the direction of tug and glider get too far apart. My experience with a cg-hook HP-11T (fixed tailwheel, no swiveling or steering)mirrors yours, but with the added problem of a wing wanting to drop and requiring prompt rudder input. I've launched from rough grass and pavement. Had to release once for the resons you state. Once in the air, no big deal. Michael |
#25
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Low tows are cool! :-)
Like many clubs in Europe mine has been to the Czech Republic a couple of times for a few weeks. I remember the first time we went there loads of people among us had to qualify for towing (as we usually do winch-launching). The Dutch towing exam includes a low-tow. The Czech exam apparently did not, because the towpilots had to be briefed on this, it was new to them. All but one of the Czech towpilots said "yeah okay!", but one objected. He thought the whole thing was crazy and if the others were going along in the whole low-towing thing that was okay, but wasn't. He left after that, but he can't have been far away when the first checkrides were done, because after a fashion he came back and was more than happy to join in. :-) :-) :-) Jasper The Hague The Netherlands "Sleigh" wrote in message ... At 13:54 24 July 2003, Geoff Vincent wrote: On Thu, 24 Jul 2003 13:02:00 +0100, 'Chris Reed' wrote: I have experience of two different kinds aerotowing from a CG hook: 1. Launching an LS4 (tailskid) from an unmade (dirt, gravel, rocks) runway. The problem here was directional control, with the glider snaking around until there was enough speed for the rudder to counter the crosswind. Not a real problem but hard work for 2 or 3 seconds. Hand on release in case the direction of tug and glider get too far apart. 2. Launching my Open Cirrus (tailwheel) from a paved runway. Absolutely no directional control problems at all. By the time the tailwheel is lifting, the rudder is working. Just be aware of the possibility of swinging once the tail comes up - whether there's any swing will probably vary between glider types, but I've never noticed anything with the Cirrus. There is, for all CG hook aerotows, the danger that if the glider gets high it will begin to winch launch itself. I'm told this will pull the tug tail up and cause more excitement than anyone wants (or worse than excitement if low down). Neither the LS4 nor the Cirrus showed any signs of doing so, but I kept a watch on the tug position ready to release if it got away from me. Sounds like excellent justification to fly low tow. Geoff Vincent Australia Geoff You know that suggestion is, far too sensible and practical ,for this group Low tow fan..England |
#26
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On Thu, 24 Jul 2003 11:52:05 -0400, Todd Pattist
wrote: Sleigh wrote: Sounds like excellent justification to fly low tow. You know that suggestion is, far too sensible and practical for this group Low tow fan..England I'm always fascinated by this low-tow high-tow discussion. Do you mind if I ask what your climb rate is on tow? I tow in my Ventus above the wake (unless on XC tow retrieve), but the L-19 tug's wheels are well above the horizon, and I'm significantly lower than the typical instructor when I ask where he tows while I'm taking a flight review. I tow in my preferred location in part for visibility over the compass mounted on my panel shield, and in part because it just "feels" right, but I really find it odd that anyone would intentionally tow below the wake of an L-19 at near sea-level during a climb to release. The rope would be over me in a heartbeat if it broke, and there's a constant strong tendency for the steep upwardly angled rope to pull up the glider's nose that would quickly lead to kiting over the towplane if there is a momentary inattention. Todd Pattist - "WH" Ventus C (Remove DONTSPAMME from address to email reply.) I'm with you Todd. The rope can kill you, let alone bits falling off the towplane and with a high powered tug and shortish rope you don't have nearly as good a horizon reference as you are looking upwards. Low tow fans note: You cannot fly low tow until the towplane is some subtantial distance from the ground. So the problem becomes where do you transition- either you fly through the towplane wake very close to the ground or do it at 200 -300 feet in which case why bother? Both introduce unnecessary hazards which are entirely avoided by flying stabilised high tow(just above the wake). Nearly all these problems go away if you use a longer rope. About 240 feet. The towplane wake has much less energy, the rocks don't ding your glider, the "in station" window is much bigger and if you try it you will find it is all a much more pleasant and relaxed experience. You even have time in the glider for decent lookout and may prevent a mid air collision, one of the main hazards for tow pilots in Australia which leads them to die at 10 times the hourly rate of cropdusters. Sailplanes are relatively safe compared to this. The pilots only die at about the same rate as cropdusters per hour. If you think there is something wrong with this you may just be getting a clue that a problem exists. Mike Borgelt |
#27
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Geoff Vincent wrote in message . ..
On Thu, 24 Jul 2003 13:02:00 +0100, "Chris Reed" wrote: I have experience of two different kinds aerotowing from a CG hook: 1. Launching an LS4 (tailskid) from an unmade (dirt, gravel, rocks) runway. The problem here was directional control, with the glider snaking around until there was enough speed for the rudder to counter the crosswind. Not a real problem but hard work for 2 or 3 seconds. Hand on release in case the direction of tug and glider get too far apart. 2. Launching my Open Cirrus (tailwheel) from a paved runway. Absolutely no directional control problems at all. By the time the tailwheel is lifting, the rudder is working. Just be aware of the possibility of swinging once the tail comes up - whether there's any swing will probably vary between glider types, but I've never noticed anything with the Cirrus. There is, for all CG hook aerotows, the danger that if the glider gets high it will begin to winch launch itself. I'm told this will pull the tug tail up and cause more excitement than anyone wants (or worse than excitement if low down). Neither the LS4 nor the Cirrus showed any signs of doing so, but I kept a watch on the tug position ready to release if it got away from me. Sounds like excellent justification to fly low tow. Geoff Vincent Australia Geoff Completely agree. Low tow easier to fly, easier to teach,never have broken a rope in over 30,000 tows at our operation, and--------- NOBODY EVER DOVE A TOWPILOT INTO THE GROUND IN LOW TOW! 9500 low tows and counting UH |
#28
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"Jasper Grannetia" schreef in bericht ... Low tows are cool! :-) Like many clubs in Europe mine has been to the Czech Republic a couple of times for a few weeks. I remember the first time we went there loads of people among us had to qualify for towing (as we usually do winch-launching). The Dutch towing exam includes a low-tow. The Czech exam apparently did not, because the towpilots had to be briefed on this, it was new to them. All but one of the Czech towpilots said "yeah okay!", but one objected. He thought the whole thing was crazy and if the others were going along in the whole low-towing thing that was okay, but wasn't. He left after that, but he can't have been far away when the first checkrides were done, because after a fashion he came back and was more than happy to join in. :-) :-) :-) Jasper The Hague The Netherlands Hoi Jasper, Ehmmm...the Low-tow in this discusion is something else as the low-tow you mean. Your low-tow is an emergency procedure where the tow plane brings the glider back in case of a malfuction of the release. The low-tow in this thread is towing in a low postion behind the tow plane (e.g below the wake of the prop). Low-tows are done in Aussie, like you should know! cu in Venlo at the juniors! greetz Patrick |
#29
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I stand corrected!
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#30
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The key issue here is that 90% of the danger to the towpilot from a
ballooning sailplane occurs before one has enough altitude to get into low tow. Granted, there may be a 'mindset' of the glider pilot to stay low, so there may be a little less incentive to get high on the tow while both are still less than 50' AGL or so. Tom Sleigh wrote in message ... At 13:54 24 July 2003, Geoff Vincent wrote: On Thu, 24 Jul 2003 13:02:00 +0100, 'Chris Reed' Sounds like excellent justification to fly low tow. Geoff Vincent Australia Geoff You know that suggestion is, far too sensible and practical ,for this group Low tow fan..England |
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