Cuddly KB2 [Archive] - Rotary Wing Forum

View Full Version : Cuddly KB2

Gary_in_Orygun

11-13-2003, 06:32 AM

Just when I kept saying that you can't cuddle a gyrocopter, someone out there proves me wrong. *Now I just need to figure out how to post the picture with this message of John Flenna at the November PRA73 meeting with his gyro. *Kevin Richey is quite the photographer. http://pra73.net/Picture_Page/11_08_03_9.jpg

Aussie_Paul

11-13-2003, 09:32 AM

Very nice looking machine. I would cuddle it to, no I would  probably kiss it when no one was looking!!! LOL With what I have learned during the last 3 years, I would have reversed the gearbox and raised the engine. It is great to have the pics available now Todd. Aussie Paul.

RayPierce

11-16-2003, 01:39 AM

Very nice Gyro.   Wouldn't it be better if the gear reduction unit was inverted?   Looks as if the there is room for the prop still. Ray Pierce PRA Chapter 13

KB2man

11-16-2003, 05:00 PM

Thanks, Thats my baby!  Can't we loose the cuddle picture.  As for my gearbox well thats the way I like it.   John KB2man

scottessex

11-17-2003, 01:41 AM

What's the real deal on the gearbox up/down argument????

Hognose

11-18-2003, 02:04 PM

What's the real deal on the gearbox up/down argument???? Hey Scott. The deal is, raising the engine a smidge and inverting the gearbox in similar gyros will put the thrustline closer to the centre of mass. You want the thrustline pretty close to the centre of mass so that you don't have pitching moments when throttle settings are changed. It's mostly a problem, though, in machines that have less horizontal stab than this one, and more power. Stabless Bensens did fine for ages with the "72-hp" McCullough (yeah, more like 40-hp, when it ran). Next thing you know people are putting 130-HP soobs on the machine, and raising the thrustline so they can swing a bigger propeller... this is a bad thing. Sometimes a fatally bad thing. The KB-2 is a lot like a Bensen and is at least as safe as that machine, with the normal range of HP (like this Rotax, which is what? 65 HP?). Stability in a gyro has a lot of ingredients and the height of the thrustline in relation to the centre of mass is an important one, but far from the only one. cheers -=K=-

scottessex

11-20-2003, 03:53 AM

Reason I was wondering, is I have a bensen, with an arrow 65hp engine and a 60" prop, gearbox up. I guess it is more like a KB3 than anything else, but the seat has been raised a couple of inches.

Kevin_Richey

11-20-2003, 07:21 AM

Well, I just popped in here and saw John's KB-2! He didn't tell anyone here when he posted that bit about the gearbox being up or down,  but he had raised the seat up like the KB-3 and says that it feels rock solid now in all aspects in the air.

KB2man

11-20-2003, 12:17 PM

Kevin, Just want to say hi . See what you started. Next you will be telling them that I taught myself to fly!  Later,  John KB2man

Kevin_Richey

11-22-2003, 03:02 PM

OK, John, I won't tell anyone that you taught yourself how to fly your gyro... If anyone wants to see KBMan flying his KB-2 gyro, go here, and click on the PRA 73 Nov.'03 mtg. folder and the John Flenna folder: http://photos.yahoo.com/kbr1954