We made it happen! First SparrowHawk autogyro is flying in Russia. Three months of interesting job and - this is it! Don't be surprised with "strange" pitch angles of the aircraft at take-off and landing - they are intentional. I will tell you about this some later...
This aircraft was assembled right according to AAI drawings and instructions
less rotor brake lever
which we moved to the center mast between crew heads. This was done for some
reasons:
1) too many controls in the centre part of cabin doesn't seem practical. Since
the rotor brake isn't used inflight it may be moved away from the closest to
pilot's hands and eyes area.
2) this mod shortens the brake cable though this reason has not very big
practical sense - you save maybe one pound of weight and make lever operating
just slightly easier. First reason was really main and
3) Putting the brake lever between pilots' heads gives you an excellent place to
hang headsets on
All other parts of aircraft were assembled without any mods - we only replaced
AN hardware with metrical (aircraft grade, sure) ones somewhere - just in case.
We measured static thrust with 72" WarpDrive and then with 69" (not 70" as I
stated in previous thread - it's really 175 cm) Lugansk prop - found that
Lugansk prop works slightly better and we can save ca.17-18 lbs weight on it.
Thus we installed Lugansk and got 280-285 kg static thrust on it, I've wrote
about this in previous thread.
Empty weight (complete with oil, coolant, radio and headsets) is 380 kg. The
only additional things we've installed are Icom A110 transciever (heavy thing -
when I ordered it I simply missed it's weight - it has a speakerphone&lifier
inside which is absolutely unnecessary in gyro), Flightcom mc403 intercom and a
couple of simple Flightcom headsets. Putting antenna in front of windshield we
also got a good point for slip strip.
Hangtest showed (20 kg of fuel):
-5.5 deg (nose down) - pilot 65 kg
-6.5 deg - same pilot plus 75 kg co-pilot
-7 deg - same pilot plus 95 co-pilot
All rotorhead and controls stops were adjusted according to AAI recommendations.
Prerotator gave us solid 180 rrpm (+15 deg C OAT) after some minor adjustments.
Prior to install the rotor we make some driving training to become familiar with
throttle, brakes and pedals.
Test pilot was Dmitry Rakitskiy, that same macho who performs Dominator and
Hunter flying in known videos. I played as a ballast in the right seat
and a voice informator on demand (" airspeed 80...85...90...120...110" etc) -
this is our old practice which helps to make testing more effective since test
pilot can concentrate more on other details of flight envelope.
Weather conditions were almost ideal: +15 deg C OAT, 55-60% RH and 5-6 m/sec
stable wind mostly
along the runway. Runway - 400 m (meters, not miles
,
concrete, +200 meters above sea level.
Due to this wind we've got 200-210 rrpm on prerotator and tried some times to
spinup rotor on low roll speeds. Rotor reacts very well, without any tendency to
flap and it takes probably 30 - 50 meters of roll to spin it up to 260-270 rpm.
Aircraft right after take-off is lazy at low airspeeds but becomes friendly
starting from 50-60 kmh. Yes, we took off at low airspeeds, lower than Jim
Mayfield recommended me - there was a reason for this which I will tell you
about some later. That day we flew at no more than 120 kmh airspeed (indicated,
cannot tell this time if this was true airspeed) and I was surprised that it
flies this airspeed at only 4000 engine rpm. Will check if things are really
that good. Rotor rpm were 300-310 @ 560 kg take-off weight.
Another pleasant thing was that rotor (fly from the box - literally) is very
smooth. No uncomfortable shake at seat/cabin nor at sticks. And we didn't note
any tendency to yaw which was mentioned here at forum recently.
Some things in controls seemed to us not very good but I'd rather discuss them
with AAI first because they (things) are probably from our own gaps on assembly
or may be from our different habits on controls.
We plan to continue testing so I hope to
place more information and photos soon.
If everything uploaded well then you can see a short video (700 kb) of SH's first pattern.
