Hi John,
What a lucky lad being able to fly to Sun N Fun! Yes it's true that things
are worse with a fixed pitch prop, but we've been loving the benefits of ou
r Airmaster constant speed for about 8 years. We always make the final appr
oach to land in fully fine pitch crossing the threshold at 55 knots or less
.
Our runway is 500m tarred but narrow, barely 15m. Even in still air with th
e prop fully fine, we use up the majority of the runway esp. when light. Cr
osswinds can be challenging on our relatively narrow strip with soft ground
/ditch/long weeds to catch the outriggers should anyone allow the 'plane to
drift too far sideways.
Scottish weather being what it is, the verges tend to remain soft for much
of the year and at least half the year the wind blows 10 to 15 knots at rig
ht angles. The annual quota of sunny days with winds light along the runway
can almost be counted on your fingers and toes. They tend to happen on wor
king days or when the wife wants something done around the house and garden
. I wonder if I can find a well-paid job in the US of A!
In the mean time I'll keep our engine settings the way they are to minimise
floating and ask my Sheila's angels to surround us in a fluffy pink cocoon
. Actually I can't see any problem with my settings; as I emphasised previo
usly, we keep the engine above 2000 rpm for all but a couple of seconds whe
n checking slow running before take off. During the glide it remains smooth
without any hint of quitting. We aren't allowing the gearbox to chatter, e
ver. Someone please prove me wrong!!
Am I green with envy? Who, me! Well at least we know that the Europa is sti
ll a brilliant little machine.
Jonathan
> Date: Tue, 15 Apr 2008 11:59:47 -0400> From: johnwigney@alltel.net> To: e
uropa-list@matronics.com> Subject: Europa-List: Re: Rotax idle speed. Tailw
wigney@alltel.net>> > Hi Jonathan,> > Thank you for your interesting and in
formative emails regarding idle > speed for tailwheel Europas. It is certai
nly true that tailwheel Europas > will float if too much prop thrust remain
s. However, if one has a > constant speed prop it does change the picture.>
> I have just returned from Sun N Fun in Florida - an enjoyable trip with
> no problems in the trusty Europa. 1100 miles round trip as the crow > fli
es, using 45 US gal of 100LL. Trip down was somewhat below the scud > but n
ever below 1,000 ft agl. Stop was in Georgia at Brunswick on the > coast. C
oming back, I had to bob and weave to dodge some showers and > rain but it
soon improved to clear blue and this time I stopped at > Waycross in Georgi
a to fill up. Waycross is just north of the Okefenokee > swamp which is a l
arge national park with lots of alligators!> > Anyway, getting back to idle
speed. Before the trip I had just finished > my annual and had replaced my
throttle cables with solid music wire. I > carefully set the idle speed an
d full throttle with the mechanical > adjustments as per the Rotax procedur
e and followed Lockwood Aviation's > recommendation of not less than 1,800
rpm which is about where I had it > previously. (Lockwood is a big Rotax de
aler here.) On this occasion, I > did not do the pneumatic synchronisation.
However, the engine ran very > smoothly. Most of the landings on the trip
were in less than perfect > conditions but I did not have any problem with
float. I normally come in > over the numbers at ~55 kts and when I close th
e throttle at the flare - > it lands. With a large passenger and a load, it
emphatically lands.> > I suspect that the big difference between your expe
rience and mine is > the constant speed prop. See > http://www.whirlwindavi
ation.com/series100.php During landing, the prop > is set fully fine for ma
x thrust in the event of a go-around. In effect, > it acts almost like an a
ir brake when the throttle is closed. I noticed > that when I had the idle
set at ~1,500 rpm on previous occasions, the > a/c used to fall out of the
air quite rapidly as I rounded out at the > flare. For this reason I usuall
y leave a little power on at the flare to > smooth the contact. Incidentall
y, there was a very nicely finished new > tri-gear at the Sun N Fun stand w
hich had the same type of Whirlwind > prop which uses a hydraulic governor
for control.> > Wishing you many more smooth landings.> > Cheers, John> > N
262WF, mono XS, 912S, 590 hours> Mooresville, North Carolina> > > ORIGINAL
MESSAGE> > From: Jonathan Milbank <jdmilbank@hotmail.com>> Subject: FW: Eur
opa-List: FW: Rotax idle speed. Tailwheel Europa> Well, there it is folks.
Andy Draper's reply below must be the last word on this matter. I don't wan
t to be guilty of suggesting something against the manufacturer's recommend
ations. Just because my experience with the way I adjust and operate my eng
ine is satisfactory, it doesn't follow that others will enjoy the same bene
fit.> Do it by the book and no-one will be able accuse you of irresponsibil
ity.> Sincerely.> Jonathan> > Subject: RE: Europa-List: FW: Rotax idle spee
d. Tailwheel EuropaDate: Mon, > 14 Apr 2008 10:49:19 +0100From: andy.draper
@laa.uk.com To:jdmilbank@hotmail.com> Hi Jonathan,> It is relatively rare t
o find a Rotax engine that will idle happily at below 1200 rpm, in my exper
ience, even with balanced carburettors, so we would always set the idle spe
ed to be around 1500rpm (between the recommended 1400-1600rpm band) on our
demonstrators. This enabled us to operate the aircraft without excessive fl
oat, but I guess that we all just got used to that set up.> > I would expec
t that gear box wear will be accelerated if the slow idle is 'chattery' but
if it's smooth and especially as you minimise the time at slow idle, then
you probably won't suffer excessively. I'm not sure, though, that I would w
ant to go into print to recommend others to set their engines up similarly
to yours if it contravenes what the manufacturer says.> Best wishes> Andy>
> From: Jonathan Milbank [mailto:jdmilbank@hotmail.com] Sent: 14 April 2008
10:27To: Andy DraperCc: editor@europaclub.org.ukSubject: FW: Europa-List:
FW: Rotax idle speed. Tailwheel Europa> Hello Andy, The emails below are fo
r your interest and comments, if you have any. If not, then I'll go ahead a
nd submit an article to "The Europa Flyer". Maybe I'm going over a subject
which has been dealt with before, in which case I apologise. Should you spy
any traps for the unwary in what I'm advocating, please let me know. Thank
s. Jonathan> > From: jdmilbank@hotmail.comTo: europa-list@matronics.comSubj
ect: Europa-List: FW: Rotax idle speed. Tailwheel EuropaDate: Sun, 13 Apr 2
d Beale and his advice that I should post these communications on the forum
are set out for you below. The four of us who have been flying G-EIKY sinc
e 1997 (865 hours in tech. log) have no problem in remembering never to all
ow the engine to idle below 1500 rpm. In fact after starting we use the thr
ottle to maintain warm-up above 2000 rpm and don't taxi below 1500 rpm. Onl
y briefly after checking the ignitions do we pull the throttle all the way
back for a couple of seconds to check slow running around 800 rpm before co
mmencing take-off. On > rounding out for a landing, the throttle is closed
fully until the landing roll is completed and re-opened once the aircraft r
eaches a safe taxi speed. Thus the percentage of time that our engine spend
s below 1500 rpm is almo> st negligible. I learned to fly on Harvards 40 ye
ars ago and clocked 274 hours on that type. The combined experience of my f
ellow group members on tailwheel machines totals in the 1000's. All this mi
ght not make us any safer than others with less time in tail draggers, but
I certainly wouldn't have been wanting to land any such aircraft in a cross
wind with the engine idling quickly. Get squarely in contact with Mother Ea
rth a.s.a.p. after rounding out is my fervent hope and intention! If anyone
has comments or criticisms, I'd be grateful for your input. Thanks. Jonath
an > > From: louise@conairsports.co.ukTo: jdmilbank@hotmail.comSubject: FW:
Rotax > 912/914 idle speedDate: Tue, 8 Apr 2008 18:58:06 +0100> Jonathan,>
Thank you for your comments regarding the article. I am grateful for your
feedback, especially about the idle speed, and I understand your concerns.
As you are aware the gearbox wear will be a problem if the idle speed is to
o low. I can see you have accepted this as a consequence for your set up, b
ut you benefit from an aircraft that is easier to keep on the ground. Norma
lly it is difficult to achieve a stable speed below 1200, and the engine wi
ll often stop if set any lower. Rotax suggest 1800RPMI think your experienc
e would be of benefit to other (if you were to post it on the Europa (Matro
nics) forum), but it needs to be backed up with the warning about increased
risk of engine stoppage and increased gearbox wear t> hat will ensue.> I w
ill bear your comments in mind when I am working on installations that migh
t benefit from our feedback in particular the mono wheel Europa..> Regards
Conrad Beale ConAir Sports Ltd www.conairsports.co.uk ONLINE SHOP +44 (0) 1
295 771088> > From: Jonathan Milbank [mailto:jdmilbank@hotmail.com] Sent: 0
8 April 2008 10:23To: service@conairsports.co.ukCc: mo@moragjones.demon.co.
ukSubject: Rotax 912/914 idle speed> > Hello Conrad, I thoroughly enjoyed r
eading your very helpful, clear and valuable articles on servicing Rotax en
gines and I look forward to the next one. Now I'm going to take the risk of
slightly contradicting something you wrote and hope you won't think too il
l of me. I know that your articles and advice are not aircraft type-specifi
c, but idle speed is a sensitive issue with Europa mono/tailwheel aircraft
during the touch-down phase. With its laminar flow wing and slippery profil
e, the Europa mono is a bit notorious for departing from the runway against
the pilot's wishes and efforts. It wil> l float after rounding out and can
easily "balloon" upwards if just a little wind gust should happen. Once th
e Europa is squarely planted on the ground with the stick held fully back a
nd the tailwheel solidly gripping the surface, then it is easy enough to ke
ep it running straight. It's during the tricky period between raising the a
ircraft nose to round out and getting well settled on the runway that direc
tional control can be awkward, particularly in a crosswind. Therefore it fo
llows that this period of floating above the surface must be kept to a mini
mum. A fast idling engine will exacerbate> any problems. I keep the carbure
ttors adjusted so that at full engine operating temperature and with the ai
rcraft standing still in nil wind, the idle is around 800 rpm and the engin
e is on the verge of cutting out. Of course this means that the engine is s
afely idling at around 1200 rpm with the throttle fully closed while glidin
g. We who belong to the group that flies this Europa are all fully aware th
at allowing the gearbox to clatter at low rpm on the ground will drasticall
y shorten its life, so we always set the throttle to keep the rpm above 150
0 after start up and when taxying. Possibl> y the reason why our monowheel
Europa has survived relatively unscathed for 11 years ( touch wood ) is tha
t we are nearly all professional pilots with a lot of general aviation expe
rience and tailwheel experience. But we all also appreciate the importance
of minimising the floating period after rounding out for a landing. Thanks
for your superb contribution to better understanding the maintenance of our
================> > >
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