Remi, I have no views nor evidence on the relative merits of different
firms propellers, just strong views on the desirability & greater
efficiency of high twist blades. Nevertheless I am surprised to hear
your views on the low twist Woodcomp blades as they had a measured
efficiency of 85% as I remember it, which I believe is an industry
standard, and my plane certainly didn't hang about in comparison to
others. I had in fact first become interested in Woodcomp back in 2000
when at the Prague fly out I saw the Europa company 914/Airmaster plane
take off together with Tom Justic's 914/Woodcomp SR2000, with the latter
climbing at what appeared to be at least 10 degree steeper gradient. It
would make me wonder whether your friend had his pitch angles set
appropriately.
It would be good to have some rigorous comparisons done, and I would
happily cooperate with my new Sr3000/N/W if someone has an Airmaster and
we find they could be swapped over without any major trouble.
Regards, David Joyce, GXSDJ
On 2017-05-16 10:33, Remi Guerner wrote:
>
> David,
> I am not questioning your measurements but your comparisons are between two
> Woodcomp
props, not between Airmaster/WarpDrive and the high twist Woodcomp. The
low twist narrow blade Wood comp is notoriously bad as far as cruise speed is
concerned. We even have one of our french Europa owner who recently went back
---From this prop to his old ground adjustable WD, because the Woodcomp was
consistently
reducing his cruise speed.
> Remi
>
> [quote="davidjoyce@doctors.org"]Remi, The comparisons I did between low &
high twist woodcomp props were rigorous, all early in the day and over water to
eliminate the risk of catching an early thermal. They were also all done
approaching
the test conditions from above, that is doing a shallow dive from something
like 100ft above the chosen altitude and then waiting for the speed to
stabilise whilst flying level. They showed a clear 5 kt advantage at low &
middle
altitudes
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=469344#469344 [1]
>
Links:
------
[1] http://forums.matronics.com/viewtopic.php?p=469344#469344
[2] http://www.matronics.com/Navigator?Europa-List
[3] http://forums.matronics.com
[4] http://wiki.matronics.com
[5] http://www.matronics.com/contribution
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