Alltrikes

So what is Part 103?  In the USA in 1982 the FAA initially define Federal Aircraft Regulation, Part 103 (see link for details). I will summarize basic requirements for trikes that meet Part 103.

1. intended for a single occupant and to be used only for sport or recreational purposes.
2. has no airworthiness certificate
3. total dry weight less than 254 lbs (115 kg) excluding floats or deployable safety devices like a BRS
4. fuel capacity not exceeding 5 US gal (19 L)
5. maximum flying speed of 55 knots (63mph, 102kph) with max power in level flight
6. maximum power-off stall speed of 24 knots (27.6mph, 44.4kph)

If all these requirements are met than the trike is a true ultralight and complies with part 103.  Regulations do vary among countries and not all countries have a part 103 the same as the USA.  The UK has a SSDR (Single Seat DeRegulated) category which is similar to our part 103 and also states a maximum weight of 115kg.  Australia has a sub 70kg category that defines a nanolight.  My apologies but I do not claim to know much about other countries regulations that apply to the lighter end of aviation.

I believe it was Jozinko that first questioned why have this group and how it is different from the "low and slow" (l&s) group.  So here is my perspective recognizing that it includes some of my own opinions.  "Low and slow" represents a flying style that is relative to particular aircraft.  A Revo with slow trimmed wing can fly l&s but its speeds are very different from say a Dragonfly (a true UL) also flying l&s.  So slow is relative. What is "low"?  Well some might define it as skimming the surface at no more than 10 ft (maybe less) and others may want at least 50 to 100 ft AGL and call that low.  So in my opinion low & slow is subjective and can be defined and pursued by any trike pilot.

In contrast, part 103 is a well defined category and within that category various trike configurations do permit some variation in flying style.  A soaring trike typically is quite light which usually requires sacrificing weight on different parts of the chassis structure, engine and even wing.  Usually wing is fairly large or at least efficient if smaller.  So most good to excellent soaring trikes are also part 103 trikes.  However, some part 103 trikes push to the limits in the category requirements and may be better designed for XC and speed and in doing so become less suitable for soaring.  Although some would say that 63mph is not fast, well that may be true relative to your trike but 63mph is the limit for ULs and that is "fast" for an UL.  There is significant variation among all trikes/wing combinations that are part 103 compliant so that various flying styles from true soaring platforms to powering XC and be addressed.

So this was only intended to be an intro or summary of part 103.  In my opinion it is perhaps the most exciting triking category to participate in.  If you come from a GA background and fly a heavy trike and have never flown an ultralight then you might want to consider it.  You will be in for a real treat.