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Engine/motor

Posted: Sun May 06, 2018 7:19 pm
by ScottyB
The Light Sport Aircraft Rule: The FAA defines a light sport aircraft as an aircraft, other than a helicopter or Powered-lift that, since its original certification, has continued to meet the following:[6]

Max. Gross Takeoff Weight: 1,320 lbs (600 kg) or 1,430 lbs for seaplanes (650 kg)
Max. Stall Speed: 51 mph / 45 knots CAS
Max. Speed in Level Flight (at sea level In the US Standard Atmosphere):138 mph / 120 knots CAS
Seats: Two (max.)
Engines / Motors: One (max. if powered.)
Propeller: Fixed-pitch or ground adjustable
Cabin: Unpressurized
Fixed-pitch, semi-rigid, teetering, two-blade rotor system, if a gyroplane.
Landing Gear: Fixed (except for seaplanes and gliders) this is from the light sport rule
An engine is a reciprocating power unit and a motor is under definition: electric. If that is so why do they list Motors as:one
But in other paragraphs in light sport the electric motor is disallowed?

Re: Engine/motor

Posted: Sun May 06, 2018 9:58 pm
by TimTaylor
Until/unless someone builds one, it's moot.

Re: Engine/motor

Posted: Mon May 07, 2018 8:18 am
by drseti
FAR 1.1 definition, "Light Sport Aircraft" includes:
(a) A single, reciprocating engine, if powered
That FAR does not include the word "motor," but it does include "reciprocating." An electric motor (even if you call it an engine) is rotary, not reciprocating. So, that pretty well rules out electric power.

Re: Engine/motor

Posted: Mon May 07, 2018 8:40 am
by 3Dreaming
TimTaylor wrote:Until/unless someone builds one, it's moot.
And no one will build or develop one for the US market until the regulation is changed. As pointed out the regulation says reciprocating engine. This was done to prevent someone from trying to install a small turbine engine. The FAA wanted LSA to be a simple to operate aircraft. The problem with the wording in the regulation it also prohibits the use of an electric motor. There are already aircraft out there with an electric motor, Yuneec and Pipistrel for example would be a contender. There has been a push to get the regulation changed to allow for electric aircraft, but the FAA is slow to move.

Re: Engine/motor

Posted: Mon May 07, 2018 10:07 am
by Warmi
Uh .. this is so frustrating.

I think it would be so much better to have FAA concern itself with defining performance standards and not implementations.
In other words , it should define performance characteristics that define a class of aircraft without defining exactly how it should be implemented - the way it is currently done pretty much guarantees that by the time they get around to approve some new technology and include it in their regulations - the market is already 2 generations ahead ( this is especially true with avionics )

Re: Engine/motor

Posted: Mon May 07, 2018 12:31 pm
by TimTaylor
Seems like, if someone had something worthwhile, they could partition the FAA and get the regulation changed. IDK.

Re: Engine/motor

Posted: Mon May 07, 2018 1:21 pm
by 3Dreaming
TimTaylor wrote:Seems like, if someone had something worthwhile, they could partition the FAA and get the regulation changed. IDK.
https://www.wired.com/2015/09/blame-faa ... airplanes/

Re: Engine/motor

Posted: Mon May 07, 2018 1:31 pm
by TimTaylor
3Dreaming wrote:
TimTaylor wrote:Seems like, if someone had something worthwhile, they could partition the FAA and get the regulation changed. IDK.
https://www.wired.com/2015/09/blame-faa ... airplanes/
I'm not sure I necessarily buy the argument that the FAA is the problem. Has anyone developed an electric motor option that will fly 400 nm on a charge, then plug into a regular 120v ac circuit and recharge 100 percent in an hour? Until they do, I don't see there is anything the FAA needs to change. If it already exist, then I agree the FAA needs to approve it.

Re: Engine/motor

Posted: Mon May 07, 2018 1:32 pm
by Warmi
This is akin to some kind of government agency mandating that all computers need to be powered by Intel 2xxx family of processors (state of the art circa 1987 ) ... How fast would computer technology progress if every time Intel ( and everyone else for that matter ) were to be required to petition that agency to make the regulatory change and then wait X numbers of years for this to happen ...

Re: Engine/motor

Posted: Mon May 07, 2018 1:43 pm
by TimTaylor
Warmi wrote:This is akin to some kind of government agency mandating that all computers need to be powered by Intel 2xxx family of processors (state of the art circa 1987 ) ... How fast would computer technology progress if every time Intel ( and everyone else for that matter ) were to be required to petition that agency to make the regulatory change and then wait X numbers of years for this to happen ...
Not even close.

Re: Engine/motor

Posted: Mon May 07, 2018 1:58 pm
by roger lee
Just so you know the FAA didn't make those rules. It was the LSA committee members which included the EAA and AOPA along with aircraft Mfg's, engine Mfg's and other interested parties. There used to be about 150 of them. Probably not that many any more.
Blame your peer's and not the FAA.

Re: Engine/motor

Posted: Mon May 07, 2018 2:10 pm
by rsteele
roger lee wrote:Just so you know the FAA didn't make those rules. It was the LSA committee members which included the EAA and AOPA along with aircraft Mfg's, engine Mfg's and other interested parties. There used to be about 150 of them. Probably not that many any more.
Blame your peer's and not the FAA.
In general true, but in this particular case, I'm not sure this is true. I forget if it was the Green Dot (EAA podcast) or Airplane Geeks, but one of them recently had a guest who worked on the committee. Apparently "reciprocating" was not in the draft and was added at the FAA's request with little thought of the future. He agreed the restriction was unfortunate and should be changed.

Re: Engine/motor

Posted: Mon May 07, 2018 2:17 pm
by Warmi
roger lee wrote:Just so you know the FAA didn't make those rules. It was the LSA committee members which included the EAA and AOPA along with aircraft Mfg's, engine Mfg's and other interested parties. There used to be about 150 of them. Probably not that many any more.
Blame your peer's and not the FAA.
I am pretty sure if the LSA committee ended up setting something like 250 knots speed limit and maximum of 4 engines ( reciprocating or not ) , FAA wouldn't just accept it ... :)

Re: Engine/motor

Posted: Mon May 07, 2018 2:41 pm
by TimTaylor
Elephant in the room. What is the current capability of an electric engine in an LSA as far as range, time to recharge, and weight of engine and battery? Don't forget to include the 100 foot extension cord that would be required.

Re: Engine/motor

Posted: Mon May 07, 2018 2:48 pm
by Warmi
That’s not the point.
Since technology changes constantly, it is simply unwise to codify implementations and frankly there is nothing to be gained by doing so.
If the goal is to limit Light Sport planes to certain category of simple and low performance planes, it is sufficient to llist/limit their performance capabilities and let the market decide what is the best way to achieve that.