Klip innie bos

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Gyronaut
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Klip innie bos

Postby Gyronaut » Tue Feb 26, 2013 9:39 pm

Why is it that GA aeroplanes can calculate their weight and balance, DA, cross reference a 'takeoff-distance required' chart and determine whether they are good to go or not but we can't do it in Gyro's? :shock:

Am I missing something? I am not talking about the 5 yr Weight and Balance certificate in your paperwork, How do you KNOW you are going to make it safely out of the field on the day?

Experience? I find that experience is what you get after you needed it most.

It would be most useful if it even gave you a Vn number in Meters where you should pinpoint your go-no/go marker or the runway. How many of us are guilty of passing that mark happily and then realising its not climbing like it should?

Enlighten us please you clever okes out there. Wouldn't it be nice if we had a simple chart, or app even, to use? App with a snapshot feature to record the calculation, date and timestamped. Auto email to your address of choice (CAA even) in the unlikely event of the evidence being destroyed in an accident.

Of course keeping in mind... "Courtesy of MikeB on http://forums.flyer.co.uk/viewtopic.php?f=1&t=10419

The density specification for unleaded Mogas (EN228) is 0.720 to 0.775. The true weight in air factor requires a reduction of 11 pips from the density, so would be 0.7189 to 0.7739. Therefore weight of 90 litres of mogas would be
64.7 to 69.7 kilos. Of course you would also have previously corrected the measured volume to 15 degC using volume correction factors 1st!


:shock: :shock: nai man, keep it simple ekse^

Come on, lets do it! Help?
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Gyronaut
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Re: Klip innie bos

Postby Gyronaut » Wed Feb 27, 2013 7:25 am

Mass & Balance without distance calc for information
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Gyro mass & balance
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mak
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Re: Klip innie bos

Postby mak » Wed Feb 27, 2013 9:00 am

Len, I do have my own gyro performance chart that I compiled, tested and verified (via the MGL's black box data) that I use when not one up and close to MAUW. This chart is a simple DA calculator as well taking temp and altitude into consideration (with an average humidity). The chart then gives you the anticipated climb rate based on your weight and density altitude, but not your take-off run or distance to clear a 50ft obstacle, which I intend to add at a later stage.
Yes I agree with you, we as gyro pilots are not strict enough with this. Perhaps we are spoilt with the wonderful machines that we fly and we feel they can do every and anything.
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PieterKotze
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Re: Klip innie bos

Postby PieterKotze » Wed Feb 27, 2013 9:34 am

Morn Len & Marius,

This is where I get really excited, when the experienced Aviators start giving Air Polution like me your special tips! Len your chart seems to be 1 that is for a tandem, can it be used for a side by side, or do you need to adapt it in some way? Marius can we have more info on the chart you have developed, it will really help. Being a dumpling myself, a 90 kg pax and 60 lt fuel puts me on mauw already, so I tend to be very careful in doing these calcs. I use the chart in the Zen1 Flight Manual which I find very effective (I copied and laminated it and keep in map pouch in Gyro), weigh myself and pax on a simple bathroom scale in the hangar and calc fuel at 0.75kg/lt 95. I used the chart very effectively in Jan from FAKT with a pax that underestimated his weight by about 10 kg (no scale) and it was midday and 31 deg, so I was borderline left or right of mauw, and used 3/4 of FAKT 19 and had to start turning out left to clear the powerlines. Without consulting the chart I would have been in trouble. If I can have a mass&balance calc too, it will really help.
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Air Pollution
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Re: Klip innie bos

Postby mak » Wed Feb 27, 2013 3:54 pm

Pieter

Just remember the attached chart is a rough guide for density altitude calculation, but should be within 200ft of correct density altitude, better than nothing.
A safety factor was built into the climb rate and I have found that it works / is the same for most gyros, or at least the ones I have flown. Climb rate was calculated @ 65-70Mph, not best angle of climb (again my own safety speed @ climb out after take off).
I would like you to test your performance against it at the above conditions and speeds and let me know.
PieterKotze wrote:from FAKT with a pax that underestimated his weight by about 10 kg (no scale) and it was midday and 31 deg, so I was borderline left or right of mauw, and used 3/4 of FAKT 19 and had to start turning out left to clear the powerlines.
Sounds like you are describing your flight with me. :wink: :wink: :wink:

Interesting that you mention the weight and balance. I obviously check my weight, but in the Xenon with all loading (additional luggage,etc) right under the mast I never thought of or experienced it to be a problem.
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Gyro Performance Chart.xls
Gyro Performance Chart
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PieterKotze
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Re: Klip innie bos

Postby PieterKotze » Wed Feb 27, 2013 4:47 pm

Thanks Marius,

I will study the chart...very comprehensive! I must say, pax=85, me=110, 70 lt fuel gives me 560 kg and the density alt chart works to a T. Also I find my Gyro to be unbelieveable well balanced, with the trim setting on about 50 % straight and level is comfortable.

Thanks for the transfer of experience, much obliged.

Pieter
Air Pollution

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