Sportcopter Prerotator

[asra]

Does anyone reckon the sportscopter prespinner can work with a Rosco head? Any things to be aware of before ordering one?(cable length is one thing I don"t know)Would appreciate advice on this.

[Brian]

Rosco has fitted a few sportcopter rotators so it could be worth the call I reckon.

[louww]

Hi Baden,There"s one installed in WA. Ross can do this setup.Lou

[louww]

More photos

[asra]

Thanks, will ask him

[Brian]

One thing to keep in mind when going for a pre rotator thats capable of spinning up around the 200 revs is that if you are operating from a strip with gravel/ shale/ stone that the higher than normal prop revs could cause debris to get sucked up damaging the prop. Another important thing to consider is the added complexity of the sport copter set up and can parts be accessed & how long to get them.I remember many times when it would have been so neat to be able to spin the rotors up to 200 revs but then I remember just how simple & easy it is to change over to a new starter motor so I"m a little undecided which is the best way to go.

[MilesW]

Another important thing to consider is the added complexity of the sport copter set up and can parts be accessed & how long to get them.I remember many times when it would have been so neat to be able to spin the rotors up to 200 revs but then I remember just how simple & easy it is to change over to a new starter motor so I"m a little undecided which is the best way to go.Not really that complex. A couple of pulleys, a belt, a flex shaft and a bendix. And a couple of bearings. The belt and bearings are available locally. Would be wise to order a spare flex shaft and bendix when you buy the first one though. Ideally, put some pressure on Ian to carry some spares. I had over 300 hours on mine without a hitch and still going, but I have heard a few shafts have been busted after only a few hours. Maybe to exuberent too often...Performance is closer to 300 than 200 revs . Around the 270/280 is typical. With just a little bit of wind on the nose you can play helicopters ;D ;D There is a lot happening at that point and it is not for the feint hearted. And a cautionary note. You will need spares if you are constantly going for max. A little over 200 is generally adequate and will greatly extend the life of the flex and bendix.About 6cents worth I reckon...Miles

[asra]

Thanks that"s good advice. Yeah the starter motor up top makes the stick shake and mounting down it the mast is just as complicated.Can take off the same distance with hand spinning (with straight Patroneys), so it"s would only be a convenience anyways.Don"t need 200rpm for most take offs. It"ll come in real handy though. Whether when a gate is open on the boundary, there"s been an inch of rain, or the ground crew "might need a hand in the next hour or so, so you better hang around" in scrub country.

[Brian]

Not really that complex. A couple of pulleys, a belt, a flex shaft and a bendix. And a couple of bearings. The belt and bearings are available locally. Would be wise to order a spare flex shaft and bendix when you buy the first one though. Ideally, put some pressure on Ian to carry some spares. I had over 300 hours on mine without a hitch and still going, but I have heard a few shafts have been busted after only a few hours. Maybe to exuberent too often...Performance is closer to 300 than 200 revs . Around the 270/280 is typical. With just a little bit of wind on the nose you can play helicopters ;D ;D There is a lot happening at that point and it is not for the feint hearted. And a cautionary note. You will need spares if you are constantly going for max. A little over 200 is generally adequate and will greatly extend the life of the flex and bendix.About 6cents worth I reckon...MilesThats good to hear Miles as I have heard very little feedback re the sport copter pre rotators. 200 revs is a pretty good start and even my old girl would be airborne in 50 yards max.My rotors are doing approx 315 in cruise so 300 revs on the ground could be very interesting to say the least BUT there has been quite a few times 300 would have made a "only barely made it" into a really easy!!

[Adrian S]

Guys,You will only get high rotor rpm( greater than 260rrpm) when using low enertia blades that are 26" or under from the sportcopter system. To get above 250 with AK or Patroneys you need to do a few mods to the prerotator ratio"s and run the engine over 4000rpm this then leads to the gyro sliding with the brakes on. Just my 10cAdrian S

[birdy]

If you have it geared rite, the rotor takes care of any tendancy to skid away.Wen im sinkn the boot into me RAF spinner [clutch cant handle more n bout 3000 erpm] i get plenty of down wash blown out frunt which makes for good breaks. Soons i shove the stick forward and rip the throttle open it takes off, just like cutn the rope.Thought this setup mita cooked the clutch or belt or screwed the shaft but its still go"n strong after ?? thousand hours.