Anonymous Enthusiast, Oct 02

Carey Beazley,
Oct 02

Pioneer IID Performance

November 27, 2002.

Thanks to those who have donated towards the testing of the Pioneer IId

Sorry for the delay in posting the results of November 20, 2002 flights.

For this flight I took the gap seals off the elevator since the curvature of the mylar was just a little too much and created a bump in some places along the hinge line of the elevator. The altimeter was set to 29.92.

The first flight of the day went to 5000 msl. On tow we did encounter some turbulence at 1500 msl.

Temperature

We obviously had an inversion so it was not a good day to do testing... but we did anyway for the practice.

The aircraft finally went into a high mush and slight break at 30 mph indicated with the stick all the way back.

Did a sample sink rate holding 50 mph for a 500 ft. descent which took 3.5 minutes secs which gave a high sink rate for uncalebrated 145.43 ft. per min sink rate. I did adjust the weight to be on the seat beside me giving a reasonable cg location for slow flight. i have not measured that position yet but assume it to be about 7 3/4" from the ground to the bottom aft fuselage.

Everything felt very comfortable with the new position of the aileron belcrank and rearward CG position. Did a run to 90 mph which felt very comfortable.

Second flight

Temperature

Timed runs

I did a number of high banked turns, checked out the roll rate and enjoyed the rest of flight.The results below are compensated for temperature and altitude but at this point becuase of the inversion and winds aloft should not be conisidered as accurate.

:

Nov 20, 2002

November 13, 2002

With the poor flying weather we decided to do some checking on our airspeed indicator. A manometer was constructed and attached to the pitot tube of the glider. The system held pressure and the pressure displacements where recorded.At 30 mph the instrument erro is +6 mph but at 60 mph it was correct. At 80 mph hour it is down by 2 mph.

Above is the very easily constructed manometer

October 27, 2002. Mat flew twice today his pilot report is as follows:

Since moving the CG back the nose wheel lifts off much quicker. When we first started flying the nose wheel seemed to be held on the ground for longer than was necessary but now it lifts off where one thinks it should.

The glider on tow hardly needs rudder, since it is somewhat held in position by the bridle. Trying to go outside of this parameter one notices that when pressing the right pedal you put tension on the right bridle and then one is pulled back to the left. Basically just using the ailerons and elevator gets the best results.

Once off tow I opened the spoilers and there was an expected nose down attitude easily countered by the elevators. Nothing more seemed to happen with fully deployed spoilers so I ran the airspeed up to over 70 mph and there was no pitch oscillations so I presume our problems are solved except for the fact than now we seem to have less drag without the lower spoilers. A full slip is now required to get a precision landing which it does predictably and very well.

The airspeed seems to read a little more accurately but we need an air calibration to really find out for sure.

I actually took the second flight just because it was so much fun to fly!

October 26,2002. Mat and Muggs have been away for the last week and a half. Mike did some flying and when Mat returned Mike and Mat did some late night thninking about the Pioneer IId.

Since waxing the wings we developed a problem with the use of the spoilers. Keeping a constant spped on final is difficult.

October 14, 2002. The weekend was a dissappointment with low ceilings satruday and high gusty winds on Sunday. However Mat took a flight just for fun.

During flight free from the tow plane I feel the CG could come back further however during the tow a heavier nose seems to help. The Pioneer is towed using a bridle from the CG to each side of the craft. This is excellent for winch or auto-towing. I would like to try a tost hook for aerotows as a comparison, however in comparison to say the 102 grob I feel they are similar in rowdy air with perhaps more aileron authority in the grob.

I am still inclined to fly the Pioneer too fast.

-mat

October 10, 2002. Mat waxed the wing and polished it before the next test flight. This was just a first coat and a second coat would have done a better job, but that was all the time he had before the flight.

Conditions at Marion, Ohio

19:37 Zulu

Wind direction at 100 degrees at 04 knots
clear, temperature was 18degress celcius
Dew point 07 degress celcius
Altimeter 30.17. density altitude was 1400 msl

temperature at altitude: 2000msl- 60 F, 3000msl-55 F, 4000msl-51F
5000msl-49F and 6000 msl -45F

The tow was absolutely smooth. there was no movement of the vario on the tow and the only minor turbulence was about 1000 agl when the tests where complete. I was able to soar on this very weak lift at 1000 agl.

Mat did an airspeed calibration at 50 mph at 5500 msl. Results were:
360 degrees-60.6 mph on the gps, 270 degrees 58.3 mph on the gps and 53.1 mph on the gps. Obviously our airspeed is reading to low...adjusted for sea level 50 mph indicated is really 60.23 mph

An Airspeed calibration at 40 mph at 5200 msl. Results were:
180 degrees -43.3 on the gps, 90 degrees -45.7 on the gps and 360 degrees 51,4 on the Gps. Again the airspeed is reading too low and adjusted for sea level the 40 mph indicated airspeed is 50.17 mph.

Mat did a 300 ft timed descent at 50 mph indicated. this took 2 minutes and 11 seconds. The true airspeed was really 60.23 and the polar indicated a 38.1 L/D. Now thats made mat a non-believer!

Mat did a timed 300 ft descent at 80 mph indicated. The true airspeed is really 90 mph and took 56 seconds. this works out to 24.64 L/D at 90 mph.

Mat then pushed the airspeed to over 100 mph and only then did he see a noticeable greater sink rate.

It did feel very remarkable! The moment I lifted off on tow I could feel quite a difference in the waxed craft. When I told Jim he just said "I've been saying that for the last forty years".

-mat

October 9, 2002. The updated Pioneer IId performance spreadsheet is now posted on the web and can be downloaded. Logger files of the Airspeed calibration, Mikes hour and a half Soaring flight and the first part of the Polar test flight are now downloadable. These files are .CAI format and just change the .CAI to IGC in the filename if your program reads IGC files.

For the Polars we did timed descents through 300 ft. We did not make adjustments for temperature, altitude or humidity on this run.

Oct 6, 2002. Mike Couts was pilot for these Tests. We calibrated the airspeed, then attempted a polar. The only flaw we ran into was that the stop watch battery crapped out on the polar run and Mike had to abort the logger to get the computer to actas a stop watch. We did however get the first part of the polar in the logger andit shows a modest 30:1 glider ratio but what was most striking was the 30:1 glider ratio at 80 mph! Cleaning up the glider should see this change in the low end.

This is the first in our series so there is a lot more data to come!

Oct 5, 2002. Mat made adjustments to the ailerons to give 2 inches down to 4 inches up on the opposite aileron. This greatly improved the handling on tow and the turns where more normal requiring a little rudder to counter the adverse yaw. The Cg is now about 7", that is the point where the glider balances on the main wheel and one measures the distance form the bottom of the rear of the fuselage to the level ground. Mike and Mat havediffering seating positions. Mike removed the rear cushion and puts the small weight under the rudder platform. Mat uses the seat cushion and has the weight at the base of the seat bulkhead.

Mat did the first flgiht of the day to test the new aileron configuration. He flew from 30 mph to about 90 mph and recorded a rough L/D of 30:1 at 65 mph. The best L/D should be at 50 mph at 35:1 and this showed a good co-relation between the theory and the practice since in refereing to the charts the theoretical L/D at 65 would be about 32:1. REMEMBER the wing loading is only 3.77 lbs /sq ft! We do nto have mylar gapr seals yet. Mat felt the Elevator should have more down so it was adjusted to from 3 inches to 4 inches down deflection measured at the root of the elevator ready for tomorrows test flying.

Mike couts did a second flight to familiarize himself with the glider in thermal conditions. He soared for one and half hours. He confirmed the better feel of the aileron adjustment and new Cg position. He was full of praise for this glider.

We won't mention that mat had a sled ride at the end of the day!

Flight Characteristics: The Marske Wing is definitely very different to fly than a normal glider. It is very responsive the the air around it and the pilot can really optimize the flight performance by the feel in the glider. In turbulence it does seem react more than the tailed gliders but it also has a far lighter wing loading whcih may account for this difference..

Thoughts on the day: What is interesting is that the pioneer IId has a wing loading of only 3.77 pounds (for mat) and yet has a glider ratio of about 35:1 at 50 mph. If we ballast it up to almost 7 pounds/sq ft., comparable to the grob 102 the Pioneers best L/D is still about 35:1 at about 80 mph but the Grob is down around 33:1 at 55 mph.. I think there is a lot to be said for the very light wing loading and the excellent airspeed of the max L/D of the Pioneer.

Oct 1, 2002

Mike Couts Flight Report:

Mat here is todays log files. You will notice things slowed down a lot.
The low speed handling and performance were very good. you can look at the
log with the cambridge software . Short flight but I was smiling all the way!

Downloadable Flight Log of sept 29, 2002 for Cambridge aero explorer software

thoughts after 9/29/02 flight

1) adjust for less differential--- suggest 1/2 inch change for starters.
2) maybe remove foam from 1 rudder cable-- fuse needs more air outlet
3) don't tow at less than 60 indicated
4) adjust for a bit more down elevator-- we have more than needed amount of up.
5) still have buzz in rudder ----check for humming bird nest.
6) use no more than 55mph indicated on final. still
a bit pitch change, learn to cope.
7) recheck my c of g w/ no cushion and small shot bag under rudder board. CG now at 7.25"? from bottom fuselage rearmost to ground. Will recheck.
8) maybe think about splitting seat cushion to allow for bottom but no back.
9) sell 4 or 5 gliders and trailers per year----- so I don't have to fix combines and tractors anymore.
10) go to bed.

-Mike

Sept. 25, 2002. Mat took the second high flight in light thermals at mid day with a 10 mph at 75degrees crossed at 10 mph . The cross wind landing was a non event.

Mat Redsell Pilot report: After Mikes flight test report I sealed the canopy, and made a cover for the rudder hinge so that it would not show an open hole on the top hinge. The bottom still had a small hole showing. I had thought of changing the lower spoilers so that they opened a little later than the upper but decided to try for myself since I suspected that at speeds of 55 or below they would be fine.

The aero- tow was fairly easy although with the midday thermals there was once when full ailerons where not enough to counter one abrupt thermal. I did not determined whether the Yaw String was correct during this maneuver. Once released I found that the CG was too far forward so one of the forward weights was pulled back which resulted in a much better handling glider. I feel the CG could even go back further but decided to give it a workout with this configuration. The Pioneer is basically quiet and I took it to about 85 mph and down below 40 mph. Turns where easy with no hint of any wing tip stall at 55 mph, and it was definitely different from the 13 meter version. I did have some difficulty getting accustomed to the rudder. It was still buzzing slightly if right or left rudder was applied and the yaw string seemed easier to correct with the ailerons.I have a suspicion that there is too much differential in the ailerons. Further testing will help determine this.

Flying at 50 mph is so quiet that one feels they are in a stall but you are still flying! I applied the spoilers and above 60 mph there is a pronounced pitch up but at 55 or lower they where easily controlled by the elevator and at times with full spoilers seemed neutral in pitch. but with a much improved sink rate to about 700 ft/min sink. A slip was a non event which further increased the sink rate. I would leave the spoilers as is although the lower spoilers need to have their springs tightened.

The L/D of this craft is very surprising, I kept tapping the altimeter just to make sure it was working since the decent rate was so low.

Ten minutes into the flight I felt totally comfortable and relaxed!

Overall this a real success! We will do a few more flights to accustom ourselves with this new Pioneer, make some changes then proceed with more testing and publicizing the results. Please help us evaluate the Pioneer IId by helping us financially to subsidize the aerotows.

-mat

Sept 23, 2002. Mike did the first high flight!

	Mike on final
Mikes Flight report: Downloadable flight log of sept 23, 2002 for Cambridge AeroExplorer software. The aero tow was almost done hands off it was so easy. Robert Mudd the tow pilot said the climb rate was about 7-800 ft a minute which is above normal for most tows. Indicated stall was at 35 mph, increased sink seemed to start at 45 mph. There is a slight left turn apparent above 70 mph. In a turn there is a tendency to let the nose come up and slow down. There is no tip stall in a turn. Elevator is neutral at 60 mph with some back pressure. This may be an indication of a nose heavy condition as the sink rate spreadsheet indicates the sink rate should increase below 36 mph.. On the negative side, the spoilers when deployed at 60 mph cause a pronouned nose up attitude. Spoilers probably need to be used below 55 mph. We will also increase the down travel in the elevator. The cockpit is very noisy with moving air and the rudder gap seals are buzzing. We will seal off the wing roots. A rough calculation of L/D is 38 at 60 mph.which is rather surprising since calculated the L/D was only about 36:1. We have not done the airspeed calibrations yet, but it is close. Further study and refinements are necessary. This is one of those moments when your financial generosity would be appreciated to help pay for aerotows.
	Mike and Robert dicsussing the aerotow.

Flight 1
Test new setting of ailerons.Try twisting the wing from the tip on the ground Watch for wrinkles in fabric to see if wing twist is a problem. fly at different speeds to see if wing wrinkles in the air.

This test completed Oct 5, 2002. No twist encountered and the new aileron setting is excellent.

Flight 2 Paid for by Anonymous enthusiast
Air speed calibration.airspeeds: 40 ,50,60,70,mph do a heading hold the speed, read the gps, do 90 degrees to that heading hold the speed read gps, do 90 degrees hold the speed, read GPS.

Done Oct 6, 2002.Corrected airspeed is on the left, indicated on the bottom

Done Oct 6, 2002