Hello Everyone,
With the discussion on MT backplates, this my be a good time to introduce
myself and ask for the group’s opinion on something.
I have a Lancair 320 and I need a new prop. There’s no point beating
about the bush: the reason is that I did a bad landing and had a prop
strike.
The engine is a Lycoming IO-320-B1A (ex Twin Comanche) and the current
propeller is a Hartzell 2 blade. It seems that some people are using the MT 3
blade instead, so I want to consider this as an alternative.
As far as I understand it, the MT prop is a little lower cost, it is
significantly lower weight, and it is 3 inches smaller diameter. On the face of
it, all these things sound good. On the other hand, I have had people telling me
that they always seem to need new blades at overhaul time – they develop cracks
at the blade root. What I haven’t had anyone tell me is what the performance
difference might be. In theory, a smaller diameter means less thrust, but the
difference could easily be outweighed by design differences.
What does the group think? Has anyone experience of switching from one to
the other?
Thanks,
Nick Long
Sent: Tuesday, June 18, 2013 1:37 PM
Subject: [LML] Re: MT Spinner backing plate
No
problems with mine, three blades Lyc IO 320, 100 hours.
Silvio Novelli
Lancair 320
PP-XSN
+55 (14)
9614-3129
On 18 Jun 2013,w 25, at 8:45 AM, Dan Ballin wrote:
Just wondering if anyone else has had this issue.
I noticed cracks
(3 of them) in the spinner backing plate of my counterweighted MT prop for my
Legacy. I have been keeping an eye on it because Ralph Love has had two
plates crack on him. I have had the prop about a year, it was dynamically
balanced. Of interest both Ralph and I have Performance engines that have been
inspected and altered ie bad parts out good parts
in.
Dan
LEG2 N386DM