Ron, I commend your approach of analysing problems before
they get you! I should probably say that I had not given
you the whole background. On our rececent Northern Lights
trip (which weathr routed round the Med) I had a problem
with the contact breaker for instruments popping, and had
isolated the guilty wire so that I at least had engine
instruments and fuel gauge. When landing on the day in
question on hearing the stall Warner going It occurred to
me to wonder whether that was on the same CB, so after
turning off the active runway I taxied fast enough
(probably 20+kts) to get the stall Warner squeaking and
pulled the CB. It was on looking back up from pulling the
CB that I found myself swerving to the right (you might
say 'serves me right at this point!) So addressing your
points:
1) Fine except killing power will reduce the down force on
the tail plane.
2) I was taxying faster than what I had been told was the
total tail wind so not a situation to shove stick forward,
and in addition I have measured airflow past back of door
at 40kts when on ground stationary at fast idle, so my
feeling is that the stick needs full back unless you are
in a gale going very slowly down wind
3) All my 950 hrs in the mono tell me to keep the stick
hard back all the time other than when gaining speed as
you take off.
4)As in a glider it becomes natural on the ground to use
the ailerons to stop the plane leaning, and this may meanR
stick to deal with R lean in following wind
5) I have the Singleton tail wheel mod (much recommended)
so can't help on those sort of problems
My comment on braking helping turning needs
enlarging. It is possible to almost spin on the main wheel
by judicious use of brake and power, but this is partly a
question of using the plane's inertia to make the C of G
which is behind the wheel, carry on round it. So braking
only encourages a turn to continue - it counteracts
efforts to stop a turn. So the clear message for me is if
started on an uncontrollable turn DO NOT brake and
consider putting in more power, unless of course that
would send you into something hard or expensive!
Regards, David Joyce, G-XSDJ
"rparigoris" <rparigor@suffolk.lib.ny.us> wrote:
><rparigor@suffolk.lib.ny.us>
>
> Hi David
>
> Thanks for sharing your experience.
>
> I am close to a zero time Mono pilot (perhaps 5 minutes
>of taxi time on a demo) so I am far from one with first
>hand experience. , but did own a Cessna 170 taildragger
>for 19 years and have flown various taildraggers along
>the way.
>
> My perception of the Europa was that it has an extremely
>powerful tailwheel steering, just need to make sure you
>keep pressure on the tailwheel and "KEEP IT STRAIGHT"
>because it does not have differential braking to save you
>if you let things get out of shape (pointer target on
>windscreen not only helps learn how to keep it straight,
>but can aid in landing additude). Whenever I fly a
>unconventional aeroplane (nosedragger), I always get
>strange looks and am questioned why am I working so hard
>to taxi a fool aeroplane on the ground. When and if the
>skygods decide to deal me conditions I would rather not
>be out in, this technique can pay a handsome reward even
>in an unconventional aeroplane.
>
> Other than that the only negative I had about ground
>handling of the XS mono is the poor turning radius (XS
>stock bell-crank), but that is only a minor inconvenience
>that I have no problem dealing with.
>
> Reading with great interest about your entry into the
>club of (those who have), if you don't mind I would like
>to do a little armchair flying about 5 concepts I have
>about ground handling of the mono. Please comment
>(comments from and put me in my place if I am off base
>and set me straight.
>
> 1) Prior to purchasing my XS Monowheel, I read and spoke
>with folks about nosing over on a mono and touching a
>wingtip and hurting the prop when you attempt to use the
>brake if you are in any sort of turn at all (including
>losing an outrigger). I made a representative model with
>scale placement of the main wheel, tailwheel and
>outriggers. It is quite obvious that if you are going
>other than straight, any turning force moves the canter
>of gravity balance on the ground to a more nose heavy
>configuration, the reason being is the outriggers are aft
>of the main wheel and when side loads begin to load an
>outrigger, the net result is moving your pivot point
>back. Being a long time mono pilot, this should be second
>nature to know not to hit the brake if in a turn? If you
>enter a serious swerve, opposite rudder, kill power if
>you have mindset and take the consequences without
>hitting the brake, unless you manage to get it going
>straight. This would be my plan, and I would practice i!
> n my mind that if I lost control, this is what I would
>do. In other words practice making my reflex to not hit
>the brake in the event of a swerve because of the well
>known consequences. Is this the wrong thing to practice?
>
> 2) I think everyone is in agreement that you want to
>keep weight on the tailwheel so you have effective
>steering. When you taxi downwind, you don't need very
>much power. When you taxi downwind the airflow will be
>going over the stabilator in the reverse direction to
>normal flight if your taxi speed is less than the wind
>speed. If that is the case then you do not want your
>stabilator full aft because that reverse airflow will in
>fact reduce the pressure on the tailwheel. On many
>tailwheel aeroplanes you would want full forward stick to
>get maximum downpressure on the tailwheel with reverse
>airflow over the stabilator. Several high time mono
>pilots say although this is true, if you add significant
>power you could reverse the flow, so they settle for
>perhaps neutral stabilator just in case you add a lot of
>power and forget to pull stick full aft. What's your
>thoughts on this practice?
>
> 3) I was planning on putting my bird in various amounts
>of wind with a direct tailwind and also a quartering
>tailwind and measure tailwheel force with no power, taxi
>power, and a larger amount of power to try and figure out
>optimal technique of keeping the tailwheel planted. Did
>you, or anyone test this? What were findings?
> I was going to do the same test with a quartering wind
>and measure the effect of full into the wind and full
>downwind ailerons. Motor off, stiff quartering tailwind,
>main on a greaseplate and tailwheel on a skateboard to
>allow EZ weathervaning.
>
> 4) Again we all know we are at a disadvantage with a
>mono because we don't have differential braking. When
>getting nailed with a right quartering tailwind, the nose
>will want to swing right. Adding a little left brake is a
>desirable thing. Thus keep the stick full left aileron so
>reverse air will push the right wing harder downwind than
>the left wing which should be the equivalent to a token
>amount of left brake. This is standard for many
>taildraggers. Is there a reason it should not be standard
>practice on a mono? It also puts a token amount of
>downforce on the upwind wing.
>
> 5) I am at a loss when I look at the cable tension for
>monowheel steering. I may be missing something, but with
>the standard XS set up, why would anyone ever consider
>having anything else than precompressed springs that
>should allow for the most precise control? It seems
>anything other than precompressed springs would be like
>driving a car with a worn rack and pinon steering
>mechanism with a lot of slop between engagement of left
>and right movement of wheels.
> Is there something I am missing?
>
> Again I have no practical experience and wish to learn
>from others on best practices and techniques.
>
> Sincerely
> Ron Parigoris
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=375842#375842
>
>
>
>
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