Two plugs - Neccessary?

Marty King mking46516 at yahoo.com
Thu Apr 21 07:20:01 AKDT 2005


I had a pilot with the same kind of plane make a
forced landing because not only did they drop out the
plugs physically were blown out of the cylinders due
to the cylinder head cracking across the top. The top
plug went through the cowl and the bottom plug made a
really big dent. I ran the maintanence shop at the
airport he made it to. After cylinder swap (I found
cracks in all four), a cowl repair and a cleaning of
the left seat the pilot was able to proceed on his
way.......

Marty
--- gene.maurice at comcast.net wrote:
> Last time my son flew his Mooney M20J Turbo here he
> had to have the plugs (8)replaced (power way down @
> 18,000ASL, two plugs dropping out). Cost installed
> $580
> 
> --
> Gene Maurice 
> AMA 3408 NSRCA 877 
> Plano, TX 
> gene.maurice at comcast.net
> 
> -------------- Original message -------------- 
> 
> > John, 
> > 
> > If I'm flying in a full-scale, I like having the 
> > redundancy of two completely separate iginition 
> > systems. :-) 
> > 
> > I'm not sure what you mean about two plugs making
> the 
> > troubleshooting more difficult. Should be easy to 
> > isolate. 
> > 
> > OTOH, changing plugs on my Dad's 182 was an
> expensive 
> > proposition. Back in the 80's, each plug was $12,
> and 
> > there were 12 plugs. :-( I have no idea what they 
> > cost now. I guess if you can afford the fuel now,
> you 
> > can certainly afford the plugs. The 182 holds 80 
> > gallons! 
> > 
> > Bob R. 
> > 
> > --- John Ferrell wrote: 
> > > Thanks for confirming my suspicions! 
> > > The only dual ignition engines that I am aware
> of 
> > > are those in highly critical applications, full 
> > > scale airplanes and emergency services. My
> personal 
> > > experience with full scale has been that the
> second 
> > > spark plug only makes the troubleshooting more 
> > > difficult. I believe the whole idea of redundant
> 
> > > ignition is a concept whose time has past. There
> are 
> > > twice as many things to fail. 
> > > 
> > > I knew a fellow who was preparing a van for his 
> > > handicapped son. The law at the time required
> dual, 
> > > isolated batteries. The mechanics acknowledged
> that 
> > > the isolation electronics were the least
> reliable 
> > > part of the van. That was many years back, I
> hope it 
> > > is better now. 
> > > 
> > > John Ferrell 
> > > http://DixieNC.US 
> > > 
> > 
> > ================================================= 
> > To access the email archives for this list, go to 
> > http://lists.f3a.us/pipermail/nsrca-discussion/ 
> > To be removed from this list, go to
> http://www.nsrca.org/discussionA.htm 
> > and follow the instructions. 
> > 
> > List members email returned for mailbox full will
> be removed from the list. 
> > 

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 
=================================================
To access the email archives for this list, go to
http://lists.f3a.us/pipermail/nsrca-discussion/
To be removed from this list, go to http://www.nsrca.org/discussionA.htm
and follow the instructions.

List members email returned for mailbox full will be removed from the list.



More information about the NSRCA-discussion mailing list