JUSTNUZZA

No replies. Someone recommended a Fullriver battery to me for engine starting but with the colder weather now here I'm finding it difficult to start, works fine in the warmer months. Further research suggests i am in need of something with a minimum of 200 CCA to turn the engine over fast enough. The fullriver is 20AH and 165 CCA. looking at an alternative YUASA or similar any ideas ?

What batteries are people using in there 912 installations ?

Sorry, did not upload very clearly.

From the operating manual.

There was something wrong it was a Woodcomp SR-3000, no end of trouble with burnt out electric pitch motors and C/S controllers. Have not heard any good reports about them. As for the RPM drop with the DUC I guess it is to do with their constant speed effect claims.

The only real benefit of the C/S prop that I had was a slightly shorter take off roll and a steeper approach angle because of the prop being in full fine. Only used to get 118 IAS 5200 rpm at 2000ft and 1200 ft min climb at 2o litres an hour. Now 125 IAS 5200 rpm at 2000 ft and 1000 ft min climb at 19.5 litres an hour. The prop is quite unusual in that it decreases the engine RPM from static to dynamic by about 200 rpm (i.e. start take off roll 5200 rpm and by the time you rotate the RPM is 5000 RPM).

Anyway, Seem to get better performance figures now with my ground adjustable prop over my constant speed useless unit and a lot less to go wrong with it.

I hope I have a better outcome than you then.

What happened to your prop ?

Wondering if anyone has installed a Duc Flash prop on their aircraft and what performance figures they are getting ? Just installed one on mine and would like to compare.

I expect that is used commonly also to boost ones ego.

Not that I am an expert or anything on this matter, But what good is a altimeter slide card when you choose a day to take off in a 20 knot headwind, even if your ability to make the turn to return to the field downwind is achieved. The extra ground speed is not going to help you with the extra kinetic energy needed to be lost to make a low speed survivable landing unless you have a reasonably long runway.

Just wondering what reference people use when they quote aircraft speeds for performance figures ? What is the altitude for reference and is the speed Indicated, True or Calibrated airspeed ?

Can I get his number please ?

I I was flying directly upwind and downwind using a burning stubble paddock as a wind reference and the GPS to indicate the minimum and maximum ground speeds in the applicable direction. Maybe I should forget about TAS and just work out wind speed from difference between IAS and groundspeed for low performance aircraft ?

No the instruments need to have there 2 year calibration done.

I am using the Dynon D100 that gives the TAS correction for IAS. The temperature probe is on the belly skin under and behind the passenger seat.

Static port is located on the side of a separate aluminium tube connected to the pitot tube.

Have a question as to the reasons for the following. I was flying today at 6000ft heading 350 indicated airspeed 110 and GPS was showing G.S of 80 knots. Turned aircraft onto heading 170 indicated airspeed 110 and GPS was showing G.S of 140 knots giving a wind component of 30 knots. Question is my aircaft has an indicated airspeed of 120 at 1000ft so my true airspeed should be 120 at 6000ft with an indicated airspeed of 110. If you try to work out the wind speed from TAS the answer is incorrect. 120 TAS heading 350 GPS groundspeed 80 knots wind component 40 knots. Heading 170 TAS 120 groundspeed should be 160 but GPS shows 140 knots ?

One cheap easy option is to download an AWS app so you can call the airfields for info in flight if you have the capability. I have a app on android that has a phone book of aerodromes to call up.

Thanks guys. Planesmaker you are right, the moment just needed to be converted from metres to millimetres and i can now get the calculations to work out.

OTE="djpacro, post: 424963, member: 369"]Need to know what the MAC is, where the datum is and leading edge of the MAC wrt that datum. Sorry can not scan documents at the moment. The MAC is 1267mm the calculation I did in the above example was empty moment 112695 plus loading moment 128.4=112823.4/take off weight 544kg= 207.395 x 100/1267= 16.36 % not 35 % ?

I have had a new prop installed on my aircraft and need to re calculate the rear C.G. The maintenance company has recalculated the empty weight moment and MAC %. I am now having trouble calculating the figures in the POH that the manufacturer has worked out. Some help would be appreciated. Original figures are as follows. C.G RANGE 24-35 % Empty weight 348kg. CG 25.5 % MAC. Moment 112695. Rear C.G Figures are: Pilot: 80kg ARM 0.6 Moment 48 Passenger: 80kg ARM 0.6 Moment 48 Bagage: 14kg ARM 2.0 Moment 28 Fuel 22kg ARM .20 Moment 4.4 WEIGHT TOTAL 196kg. MOMENT 128.4. TAKE OFF WEIGHT 544kg. CG =0.443M. 35% MAC. If I use the formula CG=Total Moment/Total weight [in] x 100/MAC [%] I can not get it right using the formula and see in the original calculation how it equals 35%. New Figures are as follows. Empty weight 343.6kg. C.G 27.4 % MAC. Moment 119251.

Another suggestion is to make terrain annunciation on terrain overlay go all the way to 10 feet instead of 500 feet just like commercial airliners.

Found out how to print A4 screenshots. I downloaded a print manager app that lets you change paper size for printing.