The one that came with it. If you're buying a used ultralight with no propeller and the manufacturer is still in business, contact them for a replacement. If they're out of business, do a web search for ultralight aircraft forums, join one and ask the membership what to get.
Working in aircraft engine intakes
At all times during operation of the aircraft.
Iraq
When your the smallest you should do things to your advantage and not give up even though your the Smallest. :)
Microsoft should and does consider Linux a threat in the enterprise desktop and server market. They are also in danger of losing market share in netbooks and ultralight laptops.
above and upwind from the heavy aircraft.
All Aircraft Manufacturers should have copies of all manuals related to their aircraft
When approaching an aircraft at night, vehicle operators should always make themselves visible to the pilot. Aircraft cannot stop suddenly and do not have great visibility.
Since aircraft do not, and in fact cannot, go into space then it should be obvious that no aircraft has ever been to Mercury, as yet.
If your unloading an aircraft, you need to be as close as possible.
There will be no apparent relative motion between your aircraft and the other aircraft. The radar readings should enable the pilots to avoid a collision between aircrafts.