Sport Copter Blade Report II

I had probably the best opportunity yesterday (Saturday) to form a final opinion as to the 2 different blades and hub-bars. I left Gillespie at 9:05 a.m. to return Dennis' Sport Copter blades to him at Ramona (14.9 miles away) and returned at around 11 a.m. flying the RAF blades. This direct comparison, within a few hours, was remarkable to say the least. I almost hesitate to post what I'm going to post, because some people are going to think I'm full of it or am a shill for Vanek. I assure everyone that the following is accurate and true and I have no other incentive than speaking the truth in posting the following.

The weather was ideal.....complete high overcast, windless and temperature about 60-65 degrees. These conditions prevailed for both legs. I leave Gillespie at 400 ft/ MSL and go to Ramona at 1500 ft. MSL. I do a cruise climb to 2,000 ft. and then level off as I come to a mountain valley with ranches. The valley is about 3 miles long and dumps me about 3 miles from the Ramona Airport.

I leveled off and set the engine rpm to around 4500. I've never had to monkey much with the pitch trim with these blades except initially, because the RAF trim required almost full nose down for level flight and the Sport Copter's was in the middle of the adjustment range. The indicated airspeed started increasing and settled on approximately 86-88 m.p.h. I checked the GPS speed throughout the length of the valley and the GPS speed ranged from 87 to 93 m.p.h. I was wearing bi-focal sunglasses, so I wasn't mis-reading the GPS.

I got to Ramona and took Dennis for a ride. I noted a little cabin and panel shake with the increased load. I left Gillespie with over 3/4ths of a tank of fuel. I did not notice any increased shake in sharp turns in either direction. There was no stick-shake or stirring. I guess I had gotten overly-picky, as Dennis exclaimed: "Holy cow! This is great. This is the smoothest gyro I've ridden in. The stick's not shaking? Are you holding it? Let me hold my hand on it. Wow."

We landed and switched the blades and after some profuse expressions of gratitude by me to Dennis for letting me use his blades for a week, I took off for Gillespie. I remembered to trim the nose down, but boy, did I miss the mark. As I started down the runway, the nose is really trying to come up. I held it down and it seemed like an interminable amount of time before the blades hit 200 rpm. I'd estimate that the aluminum blades get there in half the distance/time. After she lifted off, I started cranking in the nose down trim until she was flying normally. I stuck my finger in the hole in the side side of the trim-box, and the slider was almost bottomed out on the threaded shaft.

I flew north and levelled off before I entered the same valley. I adjusted the throttle to about 4300 and adjusted the trim a little for level flight. I should add something here. Because of the lesser rotor pitch, it takes about 100-150 engine rpm more for low rpm cruise with the Vanek blades. I'm talking of just enough power to keep the gyro from descending. I was turning about 365 rrpm with Dennis aboard and around 330-335 solo. Jim said he would add a little pitch to mine.

The airspeed indicator was indicating about 62-64 m.p.h. I checked the GPS continuously and the most I saw was 65 m.p.h. for a few seconds. It mostly showed 63-64 m.p.h. The wind was perfectly calm. The difference in low engine rpm cruise speed was phenominal, about 22-28 m.p.h. more in absolutly calm conditions with the Sport Copter blades. Believe it or don't, that's the truth.

Another observation is that I can recall feeling no small bits of turbulence with the aluminum blades. They seem to slice right through it. Small burbles with the RAFs will cause the gyro to momentarily slow down a little, the nose just start to come up, level off and then continue.....if you have a stab. If not, the nose will continue upwards, you'll have to cut throttle and wait for the nose to come down before adding power so as to be on your way. This small turbulence reaction was non-existent with the Vanek blades. I mentioned before that even in 15 knot winds, the ship flew in a very stable manner, and I couldn't tell if I was going 60 or 90 without looking at the ASI or GPS.

One thing I didn't get to try with the aluminum blades was to trim the nose down some and kick up the power. I'd venture to say that one would be able to outrun R-22s easily. If MPHA (min. power to hold altitude) gets one around 90 m.p.h., imagine what a little added power would do.

Another thing has to do with the transverse balancing bars. My suggestion would be to get rid of them. I noted a drastic reduction (about 50%) in vibes after removing them while flying the aluminum blades. I also noted that on Saturday, while flying home with the RAF blades and the transverse bars still removed, the ride was considerably smoother than when I was flying my RAF blades with them on. They don't appear to do anything more than cord-adjusting would and they add a further imbalance to the rotor system that makes for a shakier ride. Also, keep the nut on the bolt that goes through the "Magic Donut" lightly snug. Don't over-tighten it, as this will cause a shakier ride.

I am really looking forward to getting my blades. If Jim finishes a new pillow-block with double-bearings and new towers and spreader, this will be an especially awesome replacement item for the RAF. The ride was great as is, with just the blades and hub-bar. The shakes I experienced with the Vanek blades were next to nothing. The panel undulations had completely disappeared. If I had shimmed the towers to properly remove the slop, I'm sure it would have been as close to zero as one can get.

The landing flare is much easier with the aluminum blades. If you get too slow and a little too high, they will lower the ship as if it were a helicopter, rather than let the bottom drop out. They are a little more sensitive in the flare, but it just takes a little practice to keep from mildly over-flaring. One has to develop just a slightly more sensitive hand than with the heavier RAF blades.

Even if the ride weren't any better than the RAF blades can attain, the increase in efficiency is awesome. That's about all I can think of. If I left something out or there's anything else you want to ask about my experiences with the Vanek blades, fire away. I hope that I contributed to the knowledge of those contemplating new blades for their RAFs, either out of choice or necessity.

This comparison (my opinion) is only between 30 ft. RAF blades and 30 ft. Sport Copter blades. There is no way that I can comment on any other brands of blades or lengths. I know that people that fly Ernie's blades and some others are crazy about them, but Ernie doesn't make 30 footers with an 8.5 inch width, nor does anyone else that I'm aware of, except Sport Copter.

Ken's Web Page

Date: October 14, 2002 02:41 AM
Author: Paul Bruty (paulbruty@lexicon.net)
Subject: Vanek's Blades Ken it is a shame..

..that you did not use the same engine rpm with both sets of rotors. If you flew Jims blades at 4300 you would be some mph slower. If you flew the RAF blades at 4500 you would be some mph faster. That would be the real comparison.

MPHA cannot be 4500 at 90 mph. MPHA is at the best lift/drag ratio of the aircraft, approx 55 to 60 mph in a RAF with any 30' X 8 1/2" blades. MPHA speed is the speed that will give you maximum climb rate using any power setting above MPHA.

Aussie Paul.
Paul Bruty's Firebird Gyroplanes

Date: October 14, 2002 10:21 AM
Author: Ken Janulewicz (kensandyeggo@msn.com)
Subject:Vanek's Blades re: Is a shame

Paul, I don't have the technical knowledge to clearly understand what you're saying. There was a pitch and rotor speed difference between the sets of blades and I'm just using layman's terminology for what I experienced. Once I have my set of blades with a little more pitch in them, I'll be able to see what speed I get at the same engine rpm that I used with the RAF blades. Wouldn't using the same engine rpm be comparing apples & oranges, seeing as the 2 sets were pitched differently? Even at 4500-4600 rpm with the RAF blades, I never saw anywhere near 90 m.p.h., but I guess I can now try it out to make sure and ease your concern. (ha-ha). No loss. I'll just see what I cruise at pumped up to 4500-4600 or so r.p.m.

I guess I didn't understand the true meaning of MPHA. I was using it to mean the minimum power needed to hold my buttt up in the air in a cruise mode. With the lesser pitch of the Sport Copter blades, it took just a little more. I doubt that anyone can cruise comfortably at 87-90 m.p.h. at any rpm with the old blades.

I never felt comfortable near those speeds when I was testing the HS. I got up to 100 a couple times in a shallow descent and never had any desire to go there again with the RAF blades. With these blades, there's no difference in sensation when going 93 m.p.h., it feels the same as going 65 m.p.h. So everyone will have to forgive me for my lack of technical jargon and I hope the descriptions I used came through.

Ken's Web Page

Date: October 14, 2002 06:35 PM
Author: Ken Janulewicz (kensandyeggo@msn.com)
Subject: Vanek's Blades Dan B.'s Questions

Oh man. Can't you ask one question per post? Let's see. The MPHA is a term that I made up, I guess. It's not very scientific, but what I'm trying to say is that's the rpm of the engine that I can "seemingly" cruise at without descending. In other words, my slowest cruise power. Wait. Let's see....50-55 knots would be about 63 m.p.h. O.K. That's it. Enough power to hold me up at 63 m.p.h. With the RAF blades solo, that would range from about 2250-2350. I guess it is too late to see what the Vanek blades require of engine rpm to hold me up at 63 m.p.h. until I get my blades or someone else does first.

It "felt" to me like I needed a little more engine rpm with the Vanek blades to keep me up, and that translated to much more than 63 m.p.h. I think that I see what you 2 are meaning. I should have trimmed her for 63 m.p.h. with the Vanek blades to see where the engine rpm was. But my pitch will be a little increased over what I was flying, so my blades will give a better comparison when I get them rather than doing them with Dennis'.

My thinking and understanding is apparently off from the scientific terminology, but I hope you know what I mean. It "seemed" to me that just enough power to hold me up with the Vanek blades gave me anywhere from around 20-30 m.p.h. more at the top end, but I guess she was trimmed for more speed. I just didn't think of trimming with the Vanek blades to hold 63 m.p.h. I thought that I did pretty good with keeping track of what I did keep track of.

I can't imagine trimming the RAF blades for 85-90 m.p.h. Youse can go there if you want, but I'm not. I'd have the nose trimmed all the way down and probably would have to have my foot braced against the stick, pushing forward. I only have about another 3/4" of nose down trim available. I'm certainly not going to start playing with the trim adjustment now, because the Vanek blades wound up right in the middle of the pitch-trim range. I tried trimming the pitch all the way down once to pick up some speed with the RAF blades and the stick got sloppy-loose feeling and it felt "creepy." (Is that a proper scientific term?) ;>)

When I played with the tension on the donut with the RAF blades, I never could feel any difference. I don't know if what I posted was a seat-of-my-pants feeling or also taken with the RADS gear. I do know that it was very noticeable in the seat-of-my-pants with the Vanek blades that running loose was smoother than tighter. There's no way you can feel anything via your pants with the RAF blades, because so much shake is always there, it's hard to discern if there ever was a slight improvement or not. One can pretty much feel every adjustment change in cord and donut tension with the aluminum blades via your pant-seat.

I get confused too, but my terminology and explanations are the best I can come up with for now.