Keith Moore wrote:

Event History From Dick Rutan:
Remember that liquid cooled engine I was testing on my Long EZ?  We had two
failures of the coolant pump and I went back to the stock Lycoming Air
cooled engine.  The testing was continued on Atkins's Piper Cherokee 180.
(Story below)

Another reason to do R&D flt test over the desert not down town LA.

dick

=================Bob Atkins answer========
24 Apr 2003  Bob Atkins bob@liquidcooledairpower.com

 Dick,

Yes, the rumor is true.

I was flying at 4500' at about 7:00pm on Sunday, April 13th, Westbound just
off the coast near San Juan Capistrano and the failure occurred without any
warning with a huge BANG - followed by severe vibration and power loss. At
the time I was on frequency with SoCal approach and they advised that the
closest airport was John Wayne - about 18nm West of my position. [And Tower
is blind to El Toro Marine base which has shared the airspace for 50 of the
last 52 years?  Where all the local instructors practice dead stick
emergencies? Ed] The engine was only producing enough power to maintain a
400-500 ft descent at about 85mph and with the significant loss of oil
pressure along with not knowing how long the engine might continue running I
had no option but to find an off airport landing site within gliding
distance of my location. There wasn't much to choose from and I ended up
selecting I5 Northbound as my runway of last resort and turned to follow it.
I was hoping to find a parallel service road, parking lot or old bypass
asphalt to land on but there wasn't anything suitable.

When I looked ahead I saw a large, deserted concrete overpass which looked
like it was under construction (no cars visible) just coming off the I5 to
my left. As I approached I notice some large high tension line towers and
with a little more help from the engine managed to get past them. I touched
down on a straight stretch of road just after a left curve going uphill and
rolled to a stop just after the Greenfield onramp on what turned out to be
the Northbound lanes of  the CA73 tollroad. Seems that not too many people
want to pay the $3.00 toll on Sunday evening so I pretty much had the road
to myself. [He misses El Toro's 7,000' long runways ¼ mile to the right of
I5 to land on the tollroad just beyond - I keep telling people the
electronic world is not better than charts! Ed]

CHP arrived about 5-10 minutes after I landed and since there wasn't any
damage or injuries they asked me how I wanted to move the airplane. I
suggested that it could be towed to John Wayne. They called a tow truck and
the airplane was towed about 15 miles on the CA73 freeway to John Wayne with
a CHP escort. The tow was done by lifting the nose wheel in the tow truck's
wheel lift, strapping it in and rolling along on the mains at about
20-30mph. The hardest part was getting the airplane back onto the field at
John Wayne - turns out there are no gates wide enough. We ended up having
about 10 people help jiggle and pivot it through a 2
car wide gate.

Initially it looked as though the #1 cylinder head came off the barrel
however, upon disassembly I found that the steel cylinder sleeve on #1
cylinder failed. The sleeve broke clean through just below the threaded
portion of the barrel. The result was that the cylinder head with the upper
1/4 of the steel sleeve still attached attempted to depart the engine. It
didn't actually depart because the exhaust pipe held onto it but it did poke
a good size hole in the cowling. The piston became trapped in the area
between the upper and lower parts of the sleeve and on the downstroke the
rings caught the lower portion of the barrel and turned the upper portion of
the piston along with the rings into confetti. The force of the stoppage
caused the rod cap to be ripped off of the rod. The rod cap churned around
in the case and damaged the cam, cam followers and the bottom of #2 but it
didn't do any serious damage to the case. The piston and the rod remained
trapped in the barrel and didn't contribute any further damage to the
engine.

The engine kept running, albeit quite poorly and with substantial vibration
since with the #1 cylinder head displaced 2" higher than normal the intake
tube pulled out of the manifold and created a large leak. The displacement
of the head also caused the pushrod tubes to be disconnected and resulted in
a major oil leak from the lifter bores. The hydraulic lifter units were lost
overboard. Amazingly the cooling system remained intact and continued to
function until the engine was shutdown after landing. The coolant manifold
between #1 and #3 was bent but it didn't pull out of the couplers - it just
leaked a little bit.

Metallurgical analysis of the steel barrel has shown 'significant
inconsistencies' in the 4140 alloy that appear to have contributed
significantly to the failure of the steel which only had about 60 hours of
run time. Since all of the barrels were made from the same billet steel (of
German origin), I consider that all of the other steel barrels are no longer
airworthy - this includes the ones that you still have.

Since I have already arranged with another vendor to produce barrels from
forgings rather than from billet - I am confident that the steel quality
issue will be addressed in all future parts. The vendor has been
manufacturing FAA-PMA approved air cooled barrels from the same forgings for
many years.

Although the head on the failed cylinder is in perfect condition with no
signs of problems, I have decided to enhance the design of the assembly by
increasing the sleeve wall thickness, doubling the threaded mating area and
changing the thread design to one that has a much lower stress factor. The
current design is nothing more than a copy of the existing air cooled design
which was limited based on nature of the finned design of an air cooled
cylinder and head assembly. The enhanced design will also elp offset the
higher compression heads that I will be producing in

the future.

Well, that's it in a nutshell. One step forward and five steps back. I don't
expect to have anything flying again for a while until I complete the design
changes and run some more dyno time.

I would say we are light years ahead of this effort :)
I can honestly say a rotary has never ever popped a cylinder head :)
Even at the 800 HP level.

Paul Lamar

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