07/17/2001 08:35:40 AM
Thanks to everyone who has responded. To summarize the responses it
appears that the caution in pushing / pulling the plane around by the prop
is due to the danger that you might rotate the prop, thus triggering an
inadvertent engine start. This is particularly important in "GA" aircraft
equipped with magneto ignitions. With respect to Rotax engines, they don't
use a magneto, but rather a CDI ignition which requires something like a
minimum of 600 RPM to cause a spark at the plugs.........highly unlikely
that one could achieve that RPM by moving the prop by hand. Is there
anyone out there who has successfully "hand propped" a Rotax to get it
started? I'd like to know. Never personally heard of such a thing, but
who knows. I'm happy to report that no one has mentioned that pushing /
pulling on the prop puts any unusual strain on the prop hub, or on the
gearbox, which was a concern of mine. Thanks again to all who responded.
Happy pulling!
Regards,
Garry
N4220S
(813) 878-3929
FAX (813) 878-5651, Internet ID Garrys@att.com
Fred Fillinger <fillinger@ameritech.net>@post.aviators.net on 07/17/2001
12:57:23 AM
Please respond to Fred Fillinger <fillinger@ameritech.net>
Sent by: owner-europa@post.aviators.net
cc:
Subject: Re: Pulling on the Prop
Garry Stout wrote:
>
> I was sitting on the loo this morning, reading my favorite aviation
> magazine when I read a warning about "never maneuvering an airplane
around
> on the ground by pulling or pushing on the prop". For the past 2 1/2
years
> that's how I've been moving my Europa around, and that's how I see other
> Europa owners moving theirs around too. Actually, I don't have any ideas
> how I would move the plane around if I couldn't use the prop. Does
anyone
> know why we're not supposed to do this? What kind of damage could arise?
> Are Rotax powered Europas exempt from this warning because the prop is
> attached to a gear reduction box instead of directly to the engine
> crankshaft?
It's not just the gear reduction, but the "mags" on the Rotax ain't
really mags, but CDI's like on your car which, unlike your car, need X
RPM on the internal alternator (and CDI's ungrounded - switch on) just
to achieve a spark. With a Lycoming with Slick mags, and unlucky
enough to have the key on or a bad P-lead, AND the prop just so to
clank the impulse coupling, now that's a problem. But even there the
safety trick is to carefully make sure you're not in a compression
stroke, and don't turn the prop whilst pushin/pullin (on the shank of
course). Important, as here in the US, the HMO's no longer give you
the parrot for the shoulder when they install the Cap'n Hook
prosthesis for the arm you'll lose.
Regards,
Fred F, A063
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