SparrowHawk handling

[mceagle]

To someone familiar with the SparrowHawk. An experienced test pilot for the first Aussie SparrowHawk has some questions re handling. Initially the aircraft was extremely heavy in the controls, more so than you would expect because of its extra weight. The late Terry Eiland flew and trimmed it and said that in his opinion it flew fine.
The friction in the scissor joints was removed and it was a considerable improvement but still required considerable control force to manouvere.
The main thing that concerns me is that both the pitch and roll controls exhibit "oversteer". That is, once a control input is made it requires considerable opposite stick force to to hold it there and stop it going further. If released, it would tend to continue to tighten the turn or increase the pitch angle.
I assume that this is not the same for all SH's because as such they would not pass the "stability standards"

Even after 15 hours in the SH the test pilot said that he found it very hard to "grease on" a power-off landing, something that he does very well in any other gyro.
The SH is built to factory specs and has 31ft ? Sport Copter blades. Has anyone struck this problem before or are there any ideas as to the cause?

[StanFoster]

Tim: I would say that the delrin bushings inside the tunnel could be too tight. To check them....just remove the rear contol tubes and then use the cyclic in its roll mode. You can determine if its sticking...or just right...or loose. If it feels like its sticking...the cure would be to disassemble the unit and emory cloth the busihings until they are just almost at the loose point.


Mine work very nice....but if you recall my scissor arms were binding up a few weeks ago because of some anti-freeze getting into it. It handles much better now.

I agree....the controls are heavier.


Stan

[Steve McGowan]

The delron bushing were left snug on the Aussie Sparrow hawk.. I Know I Built it..These have to be fitted on the first assembly. Later on its hell to get to after the cabin is attached.

Down Yonder 25 hrs were to be flown off before it was signed off. Terry made the last adjustments. Said that it flew well after that.. The controls in my SH are very soft, not lose, but comfortable to fly..

The blades are 30' long Sport Copter (Vanick) Blades They are very good blade's BUT remember most of the SH's weight in at 900-1000 lbs or very close to it. (Empty Weight ) The SH flies well, it's very agile and responsive,,
If Ya Know What your doin..

IF NOT It's gonna handle a bit dump trucky..But so does a Cadillac

Steve




Tim: I would say that the delrin bushings inside the tunnel could be too tight. To check them....just remove the rear contol tubes and then use the cyclic in its roll mode. You can determine if its sticking...or just right...or loose. If it feels like its sticking...the cure would be to disassemble the unit and emory cloth the busihings until they are just almost at the loose point.


Mine work very nice....but if you recall my scissor arms were binding up a few weeks ago because of some anti-freeze getting into it. It handles much better now.

I agree....the controls are heavier.


Stan

[automan1223]

Steve,

Your machine and terry's flew basically the same (easy like a dream) .

However, On my check ride with Ron Menzie my shoulder got tired quick from the extra tension in the system. Do not know why but I do know if it is set up right you should be able to make it dance with 2 fingers.

Sounds like every linkage in the system should be checked for some binding, lube and recheck.

Jonathan

[mceagle]

Thanks for your replies fellas. The delrin bushes seemed fine because once the scissor arms were freed and the springs released, the controls were free and smooth. The main worrying concerns was the tendency to control "oversteer" and the heavy control pressures. Such heavy control pressures are not a good thing with a forward control head.

[Canadian Rhino]

Tim, Have you had a close look at those trim springs?
I noticed that mine seemed to bind up and sort of stick sometimes so I took them apart and rebent the insides some to stop that.
Also those springs are not up in the wind are they?

[Aussie_Paul]

To someone familiar with the SparrowHawk. An experienced test pilot for the first Aussie SparrowHawk has some questions re handling.

Tim, may I ask who this "test pilot" is?

Aussie Paul.:)

[mceagle]

Ian M. Paul.

[ptope]

check the walking arms and the main bushing in the cener that they rotate on, we had to replace ours, it was binding and made the controls very stiff, ( we believe that we slightly over tightened the bolt, therby mushrooming the bushing so it started maring the inside.) also check the right to left roll pivot, may need lubed. those are 2 areas that we had to tackle, as our controls were very stiff, now we can fly with 2 fingers.

[mceagle]

I seems that I cannot get an answer to my main concern in my initial post on this thread.

The main thing that concerns me is that both the pitch and roll controls exhibit "oversteer". That is, once a control input is made it requires considerable opposite stick force to to hold it there and stop it going further. If released, it would tend to continue to tighten the turn or increase the pitch angle

Perhaps you can help here Stan. you seem to be doing good work re the Sparrowhawk. Next time you fly could you check out the controls to see if your SH does the same thing. ie. when you initiate a turn do you have to hold opposite pressure to stop the turn from tightening?

Another interesting thing about the SH here is that the exhaust has gone from two outlets to two into one large outlet, and then finally reduced the single outlet to inch and a quarter, ond overall has picked up 200 rpm.

[StanFoster]

Tim: I have noticed that I do have to give a little anti nudge after initiating a turn. To be honest...my delrin bushing is a little tighter than others I have felt and I really believe thats the reason. When I was assembling it I wanted it a little on the tight side figuring it would "wear" in. So far its still a tad tight...but not excessive by no means. If I had to do it over again..I would have emoried that delrin bushing a bit more.

Stan

[dragonflyerthom]

One quick question...

Is there an offset at the rotor head?? This could be why it will not return without control input.

[ptope]

there should be a 2 degree offset rigged into the rotorhead when it was set up..this is done with the upper control arms. refer to the build manual, it explains this in detail...

[Aussie_Paul]

Another interesting thing about the SH here is that the exhaust has gone from two outlets to two into one large outlet, and then finally reduced the single outlet to inch and a quarter, ond overall has picked up 200 rpm.

Tim, I reckon that there has not been enough R&D re gyro exhausts. I had one made and lost 200 rpm compared to the original Raf one. Then I got another made and gained 200 rpm compared to the original Raf one.

We don't actually tune our gyro exhausts much, we mostly fit them where we can!!!!

Aussie Paul.:)

[dragonflyerthom]

Ususally The rotor will continue in the original direction of input until an opposite input is given the rotor. This can be done thru the trim/pitch adjustments or by the pilot.

[Aussie_Paul]

Ususally The rotor will continue in the original direction of input until an opposite input is given the rotor. This can be done thru the trim/pitch adjustments or by the pilot.

Thom, I can understand that the aircraft would and should stay in the new position. I believe what Tim is getting at is that if you have your hands of the stick the turn will get steeper and steeper.

Have I got that right Tim?

Aussie Paul.:)

[Steve McGowan]

Ya gotta fly high enertia rotars, they will continue with a turn if you don't counter with opposite action..

Again,, heavy iron without a hydrolic asssist will work the hell outta Ya..

in Other Words,,,

There Ain't NO POWER STEERING IN THE SPARROW HAWKS..

Like havin a FAt Girlfriend.... It Takes BOTH Hands ana LOTTA LOVIN

[mceagle]

Yes Paul, that is correct.
"offset in the head"? It is a factory head with factory setup, test flown and trimmed by the late Terry Eiland.

[dragonflyerthom]

So let me see if I am understanding this right.

Input in, Start turn, Back pressure but the turn continues to get steeper.


Is that right?

Thom

[Harry_S.]

So let me see if I am understanding this right.

Input in, Start turn, Back pressure but the turn continues to get steeper.


Is that right?

Thom


Thom;

With my machine, when I want to make a right turn, steep or otherwise, I input right stick and as the turn starts, I apply back pressure and when I attain the angle of bank I want...I apply coordinated left pressure along with the back pressure, to stop and maintain the bank angle.

When I reach the point where I want to roll out of the right turn and take up S/L flight...I will maintain the back pressure and apply left stick till I straighten up on my new heading and coordinate control pressures.

No big deal. Just coordinated control inputs.:D


Cheers :)

[StanFoster]

My honest evaluation of the handling of the SparrowHawk compared to my RAF2000.

I have been doing some good cross country flights and just returned from one today. Lots of thermal activity.

The Sparrowhawk without a doubt is much more pitch stable than my RAF....however..I had no problems with my RAF except using more stick inputs as necessary. The SparrowHawk can almost be let go of most of the time...

The RAF does not wig wag as much as my SparrowHawk. However.. its not that much and actually flies better with just using your rudder pedals as footrests.

The controls are heavier on the SparrowHawk....the RAF can be cranked around quicker...but then its lighter also. But having almost 60 hours in my SparrowHawk...it will crank around pretty dang hard....as hard as I want to put back stick to anyway.

When I was flying to Indiana and back today....it was about as relaxing as could be. I monitor stuff and am not complacent...but I am basically along for the ride. I was cruising at 3000 feet and easily maintained that within 50 feet all the way...and my heading just went off a degree or two once in awhile. If I wasnt so busy listening to Rod Stewart...I would have stayed on my GPS line .

Stan

[mceagle]

Most of your inputs on this thread were correct. It would appear that the delrin bushes were indeed a bit tight and that the "breakaway" force was greater than the friction, leading to slight overcontrol (which wouild be more pronounced with the big blades). This was no problem for a good pilot. Apparently the problem has been rectified and now the machine flies well without any vices.
If I can talk the owner into posting, he may relate some other improvements that he has made.

Thanks for the inputs.

[Brent Drake]

Stan, you fly at 3,000'msl!! Wow. I'm afraid to fly that high! In a gyro, your the slowest flying thing at that altitude. I'm always afraid that an RV or piper will come along so fast, that I will not be seen in time. I try to have a ceiling of 1,500'msl. If you get about 6,000'msl you are a setting duck for everything at that altitude is traveling about 3 times your speed.

[dragonflyerthom]

Brent

What color are your Rotors???? Now depending on the direction you are traveling will determine the altitude you will be at.. Also Do you have a transponder??? This will also give flight control you r location. Do you file a flight plan??? This will also ID YOU to flight control. If by some chance a FW is in your vicinity they will be notified that you are there and you should be OK. With white or Silver Blades they will flash to anyone in your vicinity also.
Think about it. Believe it or not the airways are safer than the roads you travel back and forth to the airport.
Now back on topic.

Thom

[Brent Drake]

Thom I know what your saying. AS ALTITUDE GOES, 3,000'msl is a IFR altitude not a VFR. Stan should be either 2,500 or 3,500

[Mike Schallmann]

I usually fly at 4500to 6000 ft MSL -- several years ago I went to 12K at El Mirage -- I like the view fom 4000AGL --it also gives me a lot of places to land in case of trouble -- Ive never yet encountered another plane at that elevation --one time I was less than 500AGL when a Tomcat passed within 500 ft of me -- he didnt see me --but to tell the truth he scared the crap outta me --it occurred in Aqua Caliente AZ --out in the middle of nowhere AZ--he passed between two low mountain peaks -just as I was coming up from the other side--- Im a part owner in a small airport there --I landed and had a beer and called it day! A friend of mine saw the whole thing --he thought I was toast--Once I got on the ground I realized how lucky I was -- he was apparently at The Goldwater Gunnery Range and was heading back to his base--

[dragonflyerthom]

Hey I for one am glad you are still around. Like the way your mind works. Your clarity of thought and you make me laugh from time to time
I probably wouldn't have had just one.
Thanks

Thom

[Steve McGowan]

Best flying I've ever done is in Buckeye AZ..

Ya gotta keep your head on a swivel ,, Crop dusters and all kinds of military aircraft is working nearby..

The entire place is likea dream..

steve

[StanFoster]

Brent: The altitude flying rule is if you are 3000 feet above the ground. I was at 3000 asl. Our elevation here is over 700 feet. If I am flying 3000 feet above the ground...I then will fly odd thousands plus 500 going easterly and even thousands plus 500 going westerly.



Stan

[Brent Drake]

You got me Stan, your right.

[KenSandyEggo]

Is it 3,000 AGL or MSL? I think it would have to be MSL. A X-country pilot couldn't be aware of every little terrain change along his or her path.

[Aussie_Paul]

What is the difference between altitude and height?

Aussie Paul. :)

[C. Beaty]

Here’s what my dictionary says, Paul.

Bear in mind there is often conflict between standard English and aeronautical English but they seem to be in agreement here.

[PW_Plack]

Ken, it's 3,000 feet AGL. (FAR 91.159)

A X-country pilot couldn't be aware of every little terrain change along his or her path...

He'd better! Otherwise, how will he avoid hitting things? That's why we have sectional charts.

This doesn't take any mental effort to do on a flight. There's nothing to say you can't observe the rule below 3,000 AGL.

If you're flying west at 4,500 MSL, and terrain below your route rises to an elevation of 1,600 feet, you are no longer required to be at 4,500, because you're only 2,900 AGL. But there's no reason to change altitude just because you could.

[KenSandyEggo]

Got it, but terrain can slowly change over a long trip, but I guess you could plan for it like we all do. Why am I even in this discussion? I never get high enough to worry about it. 500 to 1,000 AGL is fine for me.

[Brent Drake]

Paul, if your flying at 4,500 msl and 'm flying an RV at the same altitude. Looking at my sectional. I'm going to ne approching you at over 100mph. If I do not put the sectional down in time, your a splatter on my winshield. I'm like Ken, Don't fly that high, your by far the slowest moving thing at that altitude!:plane: :boom: