Pre rotating

[Ken Watson]

I read with interest about the importance being placed on prerotators. I think we are misleading new people to our sport on the value of rotor management, especially getting the blades up to speed manually. Of late there has been two serious accidents while prerotating resulting in the total loss of the machines. Both were 1st class machines with excellent safety records (ELA & MT03), but were let down by pilot inexperience. Everyone seems to be pre-occupied with how fast you can spin the blades while stationary, trying to get a short take off. Personally I think a better use of prerotaters is not to use them at all in your initial hours, and then , when you feel comfortable with your experience, spin them up to a modest speed (get them over the hump) and then taxi to get them up to flying speed. This is what everyone needs to learn. Ask the experienced musterers, they have all done the apprenticeship and hand patted blades up. I know I will have my critics, but look at the statistics and the circumstances. I had a prerotater on my machine, which I removed 250hrs ago trying to solve

[Mark Horan]

Good post Ken,Everyone knows that the hardest thing we can do in our machines is take off.Now days everyone wants bigger blades and bigger blades are harder to spin up. Pre rotators dont let the new pilot know much at all about rotor management until the rotors bite......... then its all too late.Back in the old days when I was a new student pilot, my instructor, kept smacking my hand if it ventured near the spin dry button, annoyed me at the time, but instuctor knows best.Now that I am an old student pilot, I appreciate the annoyance. really big

[Ken Watson]

G"day Mark old mate. What is a harse? Is it like a hugejarse, or smaller? Or maybe it is halfaarse? Or is it one of the three harse we learnt at school? Ken

[Des Garvin]

This old hole digg er wouldn"t have a clue what the rrpm is BUT I SURE KNOW WHAT THE ROTOR BLUR IS as that is what my good instructor taught me. Have to agree 110% with ken on this one. Des Garvin

[Tim]

Of late there has been two serious accidents while prerotating resulting in the total loss of the machines. Both were 1st class machines with excellent safety records (ELA & MT03), but were let down by pilot inexperience. Didn"t hear about these Ken - could you give us more details?

[NiqueNaque]

Ken,As usual for you, well said, I can only commend what you have said.Not only is it a good idea for a new student to pat the blades up, it is also a good idea on a windy day to do static rotor practice, to get them over the hump and let the wind wind [whined that is]

[Des Garvin]

Hi Nick, You wouldn"t have a picky of this setup would you, we had a gyro mounted up on a tow ball, it was to give me some appreciation of the control of a real gyro after I spent time on the glider. Des Garvin

[birdy]

Ya rite on the money agin Kenny. I recon every instruction machine should be manual start and stop.And for those who train in cabed machines, well, dont.You cant teach rotor management ina cab with a prespinner n taco.Iv had a few students turn up ere from the east n south with not the slightest idea of wot rotor management means.

[asra]

I recon every instruction machine should be manual start and stop.And for those who train in cabed machines, well, dont.You cant teach rotor management ina cab with a prespinner n taco.Iv had a few students turn up ere from the east n south with not the slightest idea of wot rotor management means.Zackery!. In fact, you could even disconnect the starter motor and teach em a bit of respect for the prop.

[NiqueNaque]

Des,It was quite simple, we had a real gyro and clamp / bolted a plate onto the bottom of the keel such that the ball centre was under the gyro"s horizontal centre of gravity - it would balance on the ball if you tried real hard. The ball was pointing down instead of up as they usually do on a tow bar.The Ball fitted into an upside down hitch off a trailer which was in turn bolted onto a truck steel tyre rim, this was pinned to the ground from memory, or it may have been just sitting there.The gyro was held up on blocks up until the student was established and "flying the rotor" on the ground - then the blocks would be removed to allow some movement, though there wasn"t much movement avilable - to facilitate more control.Hope this helps,Nic

[Des Garvin]

Hi Nick, Thanks for that info. What wind speeds were required to have the system work successfully?Thanks, Des

[Brian]

Ya rite on the money agin Kenny. I recon every instruction machine should be manual start and stop.And for those who train in cabed machines, well, dont.You cant teach rotor management ina cab with a prespinner n taco.Iv had a few students turn up ere from the east n south with not the slightest idea of wot rotor management means.I agree fully !!!

[Greg Mitchell]

I learnt to fly in a Raf 2000.I started off hand spinning when I soloed my Butterfly.I enjoyed spinning up the Bensen Blades, very light.I did not enjoy having to hand spin my Patroneys.Most of what has been written here I agree with and most of it has been covered before.Again, it is great to re-visit topics as new circumstances present.Whilst I agree with Birdy regarding his ideas as to the training craft not suitable to learn this very important gyro skill, I am more curious to learn how we might overcome the more obvious problems that would result should we not make use of said type craft .

[Tim]

The problem with cabbed instructors machines can be largely overcome by the instructor only pre-spinning the blades to hand speed (35-40rpm) and teaching the student to coax the blades up from there. In my opinion this should be the normal until the student gets it right every time, and only then should he be allowed to fully pre-rotate. In other words, the last step in rotor management should be assisted pre-rotation, not the first step as is now often the case.There is a problem with some machines that do not have the clearances to allow bringing the blades up without a pre-rotator and that is being looked into. There is no valid reason for a manufacturer to make them like this and it will eventually result in blade to propeller or rudder contact, with a very expensive outcome.

[Greg Mitchell]

That makes excellent sense Tim We get to keep the cabbed machines Bonus. ;DKen said:"I know I will have my critics, but look at the statistics and the circumstances."I hope not to be taken for a critic and I along with many Ken would be pleased if you could expand further on the ELA and MT03 rotor blade management mishaps/incidents.