200 rpm RAF pre-rotator

Someone modified a RAF pre-rotator attaining 200 rpm, I don't know his name, saw the video, can anyone help me find this thread?

John, is this the thread you saw? https://www.rotaryforum.com/forum/showthread.php?t=24039

Actually there are two; The one Tim mentions, and the thread by Kenny SandyEggo which uses a hydraulic cylinder simlar to a motorcycle brake. Remember there could be a problem with torque on the mast if it grabs and locks in tight.

Many thanks, I hope to have this RAF test flying by spring.

John,
Was it this video you saw?
https://www.youtube.com/watch?v=N-wiecvxZJo

Have done some work to my prerotator and got 200 out of her.
The Thread
https://www.rotaryforum.com/forum/showthread.php?t=24039

If you have any questions, you can PM me, I would be happy to help
Brad

On Edit..
Tim, I just reread the posts and seen you beat me to it!

Yes Tim,
That is the thread I saw. What I'm doing is rebuilding a rolled over RAF. It's nearing completion. They never look too wrecked but 9k in parts later I'm still ahead of the game. The only thing I don't have is a good set of radios, which will come in time. I just tried to attach a pic of it. I will have something else in the turn/bank indicator hole. I talked to a radio shop that oncerviced my bell 47, and he can outfit me for about 3k or so. All good things come with time, money, and effort. The idea of having increased pre-rotator rpm is appealing to me. I'm currently making the cheek plates, just waiting for some paint/cleaner/etching stuff to paing them since they are not factory. Nice looking panel though huh? Thanks for responding.

John, alot of the places i take off from are short, so a powerfull prespinner is essential for me.
Iv got a modified 914 powered RAF with the origional prespinner and can easily get 200+ rrpm on 30' blades.

the machine in these vids is a lite 912 machine also witha RAF spinner, and can get 280 odd rrpm on 26' blades.
TO roll for both machines can be as short as 50 paces without wind and full fuel if i need to. [ down to 30 paces on the single]

Iv dun alot more modifying since these vids were posted, and method and drive gearing are important for max effect.

These vids are the initial trials;
https://www.youtube.com/watch?v=Sc7_rjMoZM8

https://www.youtube.com/watch?v=52EWsrnItmc

Sorry bout the quality.

Geez, Birdy, how often do you have to replace your props? That dust you guys are blowing about has to eat the you-know-what out of your leading edges.

Birdy, if I understand you correctly the single seat gyro in the vid is your Feral with a Rotax 912 26'blades and an RAF prerotator setup?
You get 280RRPM before brake release and go almost immediately to WOT.

What weight does she gross out, how much fuel do you carry and what type blades are you using?

Gentlemen,
I wish to thank you for your input. If I can get 200 rpm out of the stock set up with 30' blades, that will work for me. My RAF has the 2.2 engine. Your words are very encouraging but as we all know, it's an experiment. I won't really know until I get this up and running. Currently waiting for some alluminum prep stuff so I can paint the cheek plates. Thanks again.

John, the pinner on me RAF is stock, but theres some easy fixes if you need more drive troque.

You get 280RRPM before brake release and go almost immediately to WOT.
Leigh, i can go to WOT wen the rrpm is only 200, or slightly less even.
No idea wot the ferel weighs, but its got abit of crap onit, so its heavier n it looks.
Probably 400lbs, plus 150lbs of fuel, and me. [ and im 6'6" and 4' across the shoulder ]

Sand blastn the prop tips can be a hassle Mark, unless you take appropriate steps.

Pants on fire..

Pants on fire..

birdy said:

[ and im 6'6" and 4' across the shoulder ]

Click to expand...

:lol::angel::lol:

Graeme.

Extra weight is always a problem with any mod as performance decreaces. Pardon my ignorance as a commercial pilot b ut what does wot mean? Duh, usually people come to me for their answers. When it's flyable and the paperwork is done I will have a nice long paved strip to flight test the amchine on, whether the manager likes it of not. I don't usually fck with people, but this dumb bich is so far from knowing the regs she will never come out of the fog, thinks she's running Logan in Boston. She will not be happpy to see me, and the FAA will assign that airport as they did for my other gyro. Can't pleas everybody right? If I get too mush sht my attorney will take care of things. I have a problem sith stupid people and try to avoid them. So we will see how I make out with the stock set upl Thanks for your input guys.

It means 'Wide Open Throttle' John.

This term probably occurring in the gyro world because in a fixed-wing take off, apart from the dictum that one should smoothly advance to full power at the beginning of the TO roll, it is always assumed that you will go to full power. In a gyro take off this will not always be the case immediately.

Synchronizing power application with the amount of air being allowed to feed through the rotors in order to avoid blade flap/sail may necessitate a much slower power application, or even a pause, during this phase.

Birdy your mustering requires endurance, how long does that 150Lbs last you? What rotors do you use? Patroni's?

Well, thank you very much. Now I know another term discribing an action to initiate. In my ten years of flying my little Bensen, modified drastically, I had a blast. Yes it costs money but it was cheaper than my Bell 47, I could do the work on it myself as the manufacturer, flew it in pretty gusty conditions sometimes and never had a problem with prerotation, pio, or anything. I had an engine our last summer and the place to go was a waste disposal place, made it to my spot with no trouble, just the spot was not very level, piles of bull dozed ash, and as the aircraft settled it was not very level, one wheel sank the other was a little more compacted, and the impending blade strike left the aircraft pretty distroyed. I was unscased, small scratch on my leg, but now I have nothing to fly. I picked up a rolled over RAF and am trying to get things going right the first time. As you know they are more of a cross `ountry machine which works for me. As a commercial pilot, rotorcraft, helicopter I'm not too far away from becomming a CFI, and that is what the PRA needs. It's pretty easy work, I am a tree service contractor. I've have interest in machines of all types, a pretty thorough understading of rotor aerodynamics, love the whole mess. I feel that the RAF 2000 is prone to pio and it takes some considerable instruction to get through it. Whether a stab will work or not, haven't gotten there yet, but my HS is unlike any seen on a RAF. It is well into the prop wash and just shy of being in the COT. Looks cool too. I do know that it won't hurt and it will fly, but only some flight time will tell if it puts a lid on the easy to get into pio I've experienced during initial training. Must always keep these mods in mind, and that is it is an experiment and only through procedure, observations, and conclusions will you know what, if any, flight characteristic has changed. I'm one of these guys who likes to take off with full fuel so that is never an issue. It does get hot sometimes up here, but is cold as hell in the winter, which by nature will give some performance. I'm excited at this point because I see the light at the end of the tunnel. My Bensen had a toyota starter motor for a pre rotator and it worked great, a little torquey but worked well. Also, before the ship was finished I'd stake it out and practice spinning the rotor up by hand and get it to rock on the main gear. I know some blades need a prerotator due to their pitch, but I think every gyro pilot should know how to hand spin the main rotor. That's a time when you might feel som blade flapping at an early onset and be able to stop it. It's deffinately give the new gyro pilot som experience in blade management. I had no rotor tach, used my eyes and the tip path to know when I had enough rotor rpm to begin my TO roll. People at some flyins just couldn't believe that I could fly the thing without that instrument. Time to go or I'll never stop, thanks for the reply, can't wait to be in the sky, don't know why, not flying will make me cry, by by...........

John,
Have you seen the threads discussing the Paul Bruty/Larry Boyer drop keel conversions they do on the RAFs? If you're trying to get better stability out of your RAF that would help a lot. While you're in the rebuilding process it's the best time to do a mod like that.

'One should never attempt to instruct one's maternal Grandparent in the art of extracting the umbilical juices from the ovum of a farmyard fowl.'

It appears I may have been attempting this, my apologies John.

Birdy your mustering requires endurance, how long does that 150Lbs last you? What rotors do you use? Patroni's?
Bout 4.5 to 5 hours Leigh. dependn on the work load.
Im usen AKs, extruded alu at the moment.

Makes the short TO handy for pit stops and durry? rolling... though I believe you can do that airborne.

The rolling I mean.:lol:

Dear Tim,
So many people out here now it's hard to keep track of everyone. No, I havent seen the conversion you speak of and many thanks for attaching those pics. You probably know of the sparrow hawk version, that is what I thought you meant. My opinion, the sparrow is nice and big, but it's has that dragon fly look like most drop keels. I've seen similar conversions like the one you have shown, just not on an RAF. It looks a little better than the dragon fly but it lacks sleek styling of the early bensens. Bear in mind that I am making a very subjective comment that has nothing to do with performance. In any case, If that helps a little, you know more about it than i do, then that's a good thing. My stab is right up there more so than what you have there. It was my idea to put it there, but I had someone , a long time member and friend, actually build it. I'd show you a pid but I can tell you there's nothing like it out there, it's a huge airfoil just a few inches below the center of thrust. Like I said, it deffinately can't hurt, is close to perfection with the whole dlt theory argument, and it looks cool. I haven't seen any RAFs out there with a tail like mine. Our Uncle Ray did all the trick work, charged a reasonable price, and I have to do the finish work. It's close to eing painted and when I get that far post some pics. When I first saw it I told uncle Ray that when other RAF owners who are thinking about putting a stab on, they will want this one. Starting with a new RAF rudder, it's 2k to make. You'll like it too. But thanks for those pics. I've seen other gyros with that style fly and it looks like it works well for them. My mod Bensen had one, never got a swing out of it, even if 27 mph winds. It's about to snow up here so I have some , to do. It's great being able to access everyone.