Sport Pilot Talk

bryancobb · Posted: Tue Jan 24, 2012 2:24 pm Post subject: My Mini-500 Exploits

Not really Sport Pilot Stuff, but here's some fun stuff.

Here's a few of my Mini-500 Missions from 1997.

Just remember... this was BEFORE Digital Video, MPeG's, HD, and Go-Pro Cameras.

LANDING AT AMMOCO/WAFFLE KING TO EAT
http://www.youtube.com/watch?v=qapyDexE9ps

AGGRESSIVE CONFINED AREA APPROACH INTO MY YARD
http://www.youtube.com/watch?v=GpjIpI_svbo

AT BP AT THE PUMPS GETTING GAS
http://www.youtube.com/watch?v=59VygkwrBmg

PUSH-BACK AND ABOUT TO LEAVE THE GATE AT BP
http://www.youtube.com/watch?v=E8qJieb_AxU

KSCessnaDriver · Joined: 25 Jan 2009 Posts: 159 Location: KOJC

I would love to have one of those. I know people say they aren't safe, but they look like a blast, especially since people are now fitting turbines to them.

bryancobb · Posted: Fri Jan 27, 2012 3:37 pm Post subject: Yep

KSCessnaDriver wrote: I would love to have one of those. I know people say they aren't safe, but they look like a blast, especially since people are now fitting turbines to them.

I have been aviating for almost 30 yrs.

That 8 months flying the Mini-500 was THE MOST FUN I EVER HAD!!!

The problems with the design could have easily been overcome, but the owner of the company chose a path that accused all the owners/builders/suppliers of being THE PROBLEM. He says he did remedy every design problem, but in reality, he was adamant that IFthe owner had built correctly, or IF the bearing engineers had called out the right part, or IF the ______ supplier had not told us wrong...

And on-and-on...

500+ mad customers out of 500+ total customers and the company was destined to fail. As the cash-flow started to decrease, Revolution's actions seemingly became more and more irrational.

The fate was sealed.

KSCessnaDriver · Joined: 25 Jan 2009 Posts: 159 Location: KOJC

I've spent a lot of time reading over NTSB reports about the helicopter and have came to the conclusion that the engine simply wasn't up to the task being asked of it, without careful monitoring of the engine parameters. The guys who are now putting the Solar turbines (like a helicycle) in the mini-500 seem to be having a much more reliable helicopter.

bryancobb · Posted: Sat Jan 28, 2012 5:30 pm Post subject: 2-Stroke in Helicopters

One of the real +'s of the Mini-500 was suppose to be the economical $10-$15 per hour operation cost.

The Solar burns 12 or 13 gal/hr at about $4/gal. Three times as much.

I was 185# and flew 100 hrs on the Rotax. It ran at 6,200 RPM constantly. You had to be a very knowledgeable, methodical 2-stroke engine guy, and understand all the weird things that happen just because it's in a helicopter.

The main engine problems were proper jetting, especially during normal descents where the midrange jets are metering the fuel & oil, and the RPM is still at 6,200 even though throttle has been decreased.

Several bearings in the rotor head feathering mechanism and both gearboxes were incorrect for the application and loads. Then there were a few problem areas that needed to be re-engineered, such as the mid point T/R driveshaft bearing method of attachment to the hollow aluminum shaft.

As I said, all of this could have been easily overcome, but in my humble opinion, Mr. Fetters really was not the right type person to do that. He was a Legend in His Own Mind and never felt he did anything wrong. He protected his design by requiring all buyers sign a contract that strictly prohibited the slightest deviation from his design.

As an owner/builder would find an issue and try to make the design better with their modification, he'd sue them. Joe Rinke put a Solar turbine in one. Mr. Fetters sued him and got a judgement that prohibited Rinke from flying his helicopter.

Frames started cracking where the transmission was hard-mounted because the long mast had a lot of leverage and was flexing the tubes when cyclic forces acted on the mast. He blamed the problem on all the owners/pilots and said they didn't balance their rotor adequately.

Later, a triangular "mast support" was sold that fixed the real problem of the long mast flexing the frame. The accusations of inadequate balancing had already damaged the customers' attitude toward Mr. Fetters, and the customers bagan to blog about the bad stuff.

IF the situation had been handled better, there'd be 25,000 Mini 500's flying all over the world now.

The little helicopter looked like a MILLION BUCKS. It was sexy. From the ground, when one flew over, you couldn't tell it wasn't a $2 Million MD500, until you heard that Rotax SCREEEEMING.