No "official" statement as to why OMB was going to reject it. FAA "pulled it" from OMB at the last second when they found out OMB was going to reject it. If FAA had not pulled it, then the whole process would have to pretty much start from scratch again.
The most likely reason was due to FAA's inaccurate statements of costs/benifits. The proposal was stated to cost 40 million dollars over the next 10 years with a benefit of probable lives saved of 83. The cost to "ultralight" manufacturers to become compliant with ASTM standards would put the average preconstructed aircraft at over 60 thousand dollars.......thereby actually reducing the numbers of independent (former Ultralight) flight instructors. Just as with Recreational Pilot, the current G.A. Flight schools have stated no interest in this type of instruction and for obvious economic and insurance reasons would not purchase an LSA sport Aircraft or, even purchase an older Standard airworthy aircraft like Taylorcraft or Piper cub to provide this instruction. As for "transitioning" pilots (those currently certificated, but without current medical), the FAA could easily have written into Recreational Pilot an increased limitation for airspaces /speed/ passengers into that pilot classification that would allow these pilots to continue to fly with just a State drivers license and no medical. Other than that, current Privet pilots may ALREADY transition to motorgliders with only 3 hours of transitional training. These motorgliders (called self launch by FAA) have all of the abilities and more of any currently proposed Sport Aircraft. Many, like the Europa, Xenos, Pipistrel and Grob109 are every bit airplane (2 seat side by side tractor 4 stroke engines, tricycle gear With the transitional training, here is the best part. There are NO limitations to Airspace Speed, Altitude Night flight And no endorsements required for tailwheel and complex. Not even a Sea plane rating is required if on floats. (yep, there ARE seaplane gliders) no ELT requirements as is for airplanes no Mode C transponder required in the veil or above 10,000 ft. Heck, you can even fly into some class A areas without an IFR rating or instrumentation. And, the 3 hours transition training serves as a BFR (that they will need any way) And, there is no endorsement requirement for EACH Make and Model aircraft as is for Sport Pilot Chuck
