Regarding point 2,.... not necessarily so.
According to research reported in NACA Paper no ** (haven't got no. to hand
currently, but will find if you're interested), the amount by which the
monowheel retracts (i.e. with 1/2 to 1/3 still hanging out) provides
insignificant drag reduction. Added to which there is probably a lot of drag
caused by circulation of air in the wheel well, although your fairing (if
also well sealed around the edges of the wheel) had no benefit.
Duncan McF.
----- Original Message -----
From: "Terry Seaver (terrys)" <terrys@cisco.com>
Subject: RE: Europa-List: Hey Guys...Speaking of drag...
> <terrys@cisco.com>
>
> No one has said anything about the XS cowl. I would bet that is where
> the most improvement in drag reduction could be made. Besides having
> rather poor cooling characteristics, I believe it has rather bad
> aerodynamics. For example;
>
> 1) After very carefully fairing our monowheel in, we found no
> improvement in cruise speed. We suspect because the lower cowl is
> messing up the air so badly in front of the main gear (mono-wheel).
>
> 2) In a recent magazine article on a mono-wheeled motor glider, they
> said they measured no difference in glide ratio, gear-up vs gear-down,
> again, I suspect because the lower cowl is producing copious amounts of
> turbulence in front of the gear.
>
> Just my $.02,
> Terry Seaver
> A135 / N135TD
>
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] On Behalf Of Duncan
> McFadyean
> To: europa-list@matronics.com
> Subject: Re: Europa-List: Hey Guys...
>
> --> <ami@mcfadyean.freeserve.co.uk>
>
> I found a 9+ mph speed increase from fitting spats to 500x5 wheels on my
> TD.
> I got a further 10 mph from leg fairings, but in this instance you have
> to bear in mind that the rectangular section gearleg provides about 50
> sq. ins of flat plate area; whereas the tri-gear legs present an
> elliptical section to the relative airflow.
>
> Further, the low point of application of undercarriage drag means that
> an equal and opposite moment has to be provided by the tailplane,
> creating more trim drag. So the effect of the fairings was a win-win
> benefit.
>
> Have not found anything like as much gain in any other single area of
> drag reduction.
>
>
> Duncan McF.
> ----- Original Message -----
> From: <BEBERRY@aol.com>
> To: <europa-list@matronics.com>
> Subject: Re: Europa-List: Hey Guys...
>
>
>>
>>
>> Speed Kit,
>>
>>
>> Still no answers! I am fitting my speed kit to my Tri Gear and still
>
>> hoped
>> that someone would tell me if I am doing this to gain extra
>> performance/better fuel figures , or am I just doing a cosmetic job?
>>
>> Any more comments?. The correspondence has been interesting and I
>> suppose
>> that we shall only get subjective points of view on many aspects of
> the
>> aeroplane but the question of whether a speed kit is effective,
>> performance wise,
>> should be relatively easy to answer - or do I have to wait until I
> can
>> get
>> airborne again.?
>>
>> Please !!!
>>
>> Patrick
>>
>>
>
>
>
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