Hi Guys,

To those of you that do not know I had an "interesting" experience last August in my Helicycle. I was getting very comfortable with the machine and decided to do some autorotations. So, at 600 AGL and 65 MPH I rolled of the throttle to split the needles and lowered the collective. All was well with the rotor RPM in the middle of the green. About 100 ft into the auto the rotor RPM began to decay slightly, so I lowered the collective another inch or so and that is when all hell broke loose.

The helicopter went into an immediate shake that resembled a paint can being shaken at a hardware store. It also felt like someone had a jackhammer on my head. The machine was shaking so fast and hard (about 20 oscillations per second and roughly 3-4 inches per oscillation) that I could no longer see anything other than the basic contour of the ground that was fast approaching.

Anyway, I did the only thing I could and continued my descent hoping that it would hold together for the remaining 500 ft. About 50 ft from the ground I pulled the cyclic full aft and pulled full collective hoping not to die. You could not gauge the decent rate or the attitude, so a normal autorotation recovery was not possible. At this point I just wanted to hit the ground softly. Anyway, by the grace of God I did a perfect run on landing at roughly 40 MPH or so. I left a 100 ft skid mark down the runway and zero damage to the helicopter due to the landing.

So, there I am in the middle of a 5000'x100' runway with me still alive and not sure of what just happened. I shut the turbine down and got out of the helicopter to take a look. The first thing I see is that both batter boxes broke in half and were now laying on the tail rotor shaft and attempting to cut it in half. Next, I noticed the engine mounts moved about 2 inches aft. Looking further I found that the cabin had shaken enough to slam into the frame repeatedly causing minor damage. Finally, I noticed that the main rotor shaft hood area had actually stated to tear in half at the welds.

As I was looking at the damage two guys in a golf cart came flying out to see me. One of them was a helicopter pilot and asked if I was OK. I said "sure, but look at all this, what could have happened?" He then asked again, "are you sure you are OK, because 1 minute ago I was looking at a guy in a helicopter that looked like a ragdoll being shook by a kid. I figured you were dead and then you pull of this impossible recovery. If I were you I would be on the ground in the fetal position crying like a baby. Are you sure you are OK?????"

I said yep, not a problem. So, I go home and tell my wife I almost died. She said, "what happened this time." She knows the routine I guess.

Anyway, I sent the helicopter out to be modified. Seems that I am not the first to have this happen to; however, I was never told about to recover. If had had simply rolled the throttle back on and pulled collective the shake would have went away. But this is only how to correct the symptom, not the problem.

The problem lies with two things: The main rotors are asymmetrical and must be balance 25% of mean cord, period. Not 27%, not 26.8% - 25%!! My blades were painted and were too tail heavy due to the paint. When you change the relative wind across the blades quickly (like in an auto) you run the risk of "pylon whirl" that I experienced. Had the blades been balanced correctly this would not have been a problem. Next, the old motor mounts were not secure or stiff enough. Once the blades starting flexing (we are talking 2 foot of flex up and down 2x per rotation) the engine then is subject to this motion. The mounts being weak allowed the engine to get into this same oscillation and caused even further chaos.

Finally, we had to use a sledge hammer to get the main rotor bolts out of the grips. It seems that I over sped the main rotor (duh, could not read the gauges) and bent the 1/2" bolts 41 thousandths! A few more seconds and there would be no more bolts to worry about

Anyway, I installed the updated mounts, new rotor blades, new grips, new cyclic mixers and pushrods, etc. Lots of other improvements as well. Will be balancing the blades this weekend with my new dynavibe balancing system. Looking forward to cheating death again

Actually, it is a great machine. I have never had this much fun flying. Just need to tweak it the way it should have been to start with. here are some pics:

This thing is addictive:

[youtube]http://youtu.be/wvgVjkKlatA[/youtube]

I wondered what happened to you. Glad it all worked out. Have missed your posting about the wild adventures.

Looks like a blast, Todd! Glad you're up and whirling again.

Holy crap, Todd. Glad you're ok. Glad you're posting again, too.

Welcome back dude!!

Todd BT hasnt been the same without you. We darn near lost you this time. You must have 9 lives.

Todd for Mayor?

I would love to get my Rotorcraft signoff but man it's so expensive and I don't know of any place that rents copters so then I would have to buy one and I've heard they are super expensive to maintain.

Chad,

The Helicycle is an Experimental Amateur Built which means that you do not need a rotorcraft license or signoff to fly it. You only need to hold a minimum of a Private rating in fixed wing or rotorcraft to legally fly it anywhere you want without a signoff. Go get 10 hours or so of dual in an R22 or 269A for $3,000 and buy a Helicycle for $50k or so. You only need the rotorcraft rating if you are flying an experimental rotorcraft and have a passenger as well.

The Helicycle costs less to maintain than a Cessna 150. My friend has over 250 hours on his and has spent less than $250 in three years. That includes oil changes and parts. He will be looking at a $500 bill next year for new elastomeric bearings, but that is about as expensive as it gets. The T62 turbine will run forever. Figure $10 per hour in maintenance maximum including reserves and another $65 per hour in fuel costs for a total of $75. You can't fly a 150 for that amount.

Now, if you want a reliable two place helicopter you about need to purchase a R22, 269A, Brantly B2B, Enstrom 280, etc. They are anywhere from $50-$250k. The real problem is the 12-year timeout on the Robinson that requires $100k at the end of 12 years. The Enstrom has 5-year bearings that are $6k and expensive engine repairs. The Brantly is unsupported currently, and the 269s have fairly expensive parts if they need repaired. You are realistically looking at $200/hr in any of them without insurance. Insurance can run another $6-$15k per year.

Another good experimental is the Mosquito XE. Again, no rotor rating needed and they can be had for under $40k and only burn about $20/hr in fuel. They even make a Mosquito XEL on floats that is ultralight legal!! You can fly it with no license at all.

Awhile ago, you mentioned somebody was working on a new windscreen/canopy that didn't have the huge blind spots. Any news on that?

Andy,

Yes, there are a few options. If I keep the machine I intend on replacing the entire upper cabin with a blown acrylic form. It would really help with the visibility. Once you get accustomed to the way it is now it is not too bad, but it would be much better with an unobstructed view.

I keep looking at these MD 500c machines and think I have to have one. I have to keep telling myself - NO!

Andy,

Loved your post- glad all worked out. Would love to get some type of Helio (have 5 hrs. In R44) but costs scare me a little. Have you ever checked out the hillier? or Bell 47? Need something for 2-3 Pax, good useful, etc.

Would love to learn from those who know much more than me.

Thats my next challenge, would love to get my Helicopter licence.
Whats the best chopper for a private 4-5 passengers?

The Hiller and the 47 are good machines, but they are so dang slow and parts are getting scarce for them. About 65-70 MPH is pushing it. I like the Enstrom 28F or the 280FX for 2-3 persons.

In my opinion, the Hughes/MD 500 C/D is the ultimate private helicopter that is still "affordable" at the $500k range. It is the Ferrari of the helicopters with room for 4. The 206 Jet Ranger is more practical and will seat 5 pretty easily.

Now, a Bell 222 is very affordable at $400-$500k, but they have 2 turbine engines to feed and retractable gear. They are great, though.