August 20, 1998
Exhaust system cracks
All Pulsar I XP aircraft with SkyStarís P/N 69296.000 exhaust
SkyStar Aircraft Engineering
have received several reports of cracks developing in the stainless
steel exhaust system produced by SkyStar for the Pulsar I aircraft with
the Rotax 912 engine. Because the engine mount in this aircraft is the
lower cowl and made of fiberglass, special attention must be given this
situation due to the remote possibility of heat-caused failure of the
engine mount structure and subsequent loss of control of the aircraft.
are continuing to gather information about problems with the XP exhaust
system. If you have encountered any difficulty with this system, either
in installation or in operation, it will help us to arrive at an
expedient and cost-effective solution if you contact us with a
description of your problem. If the system has cracked, a detailed
description (or photo, if available) of the location and extent of the
crack is very useful.
this issue can be resolved, we must insist that this exhaust
installation be examined carefully before every flight. Pay particular
attention to welds, bends, and flanges. Use a flashlight and inspection
mirror as necessary to view all areas of the exhaust components. Any
contact between vibrating exhaust components and stationary airframe
structure must be remedied before the system is put in service. Even
light and occasional contact of this type can be detrimental to the
integrity of the exhaust system.
you have information to offer or questions about this bulletin, contact
SkyStar Aircraft at 208-454-2444. Ask for engineering, and state the
nature of your call.