Buying an Expiremental amateur built and I want to fly it as a lsa

Discussion in 'Rules and Regulations / Flight Safety / Better Pil' started by chuckparker, Apr 3, 2015.

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  1. Apr 3, 2015 #1

    chuckparker

    chuckparker

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    I'm interested in buying an already built Sonex. According to Sonex all of their models are built and registered as EAB expiremental amateur built and can be flow as a LSA without a medical. What do I need to be careful of as far as checking the air worthiness registration. And lastly Sonex really only approves the three engines. Would an engine outside of the VW or Jabaru change this equation, so for an example a Corvair. There seems to be some of them out there as well.
     
  2. Apr 3, 2015 #2

    TFF

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    For an E-AB the phase 1 stall and top speed along with weight need to be looked at. If any don't fit LSA rules the plane can not be flown LSA and cant be converted to. The info will be written in the logbook on one of the first pages. I think anything but a vw makes a Sonex too fast to be LSA.
     
  3. Apr 3, 2015 #3

    radfordc

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    Absolutely not true!
    Sonex -- The Sport Aircraft Reality Check!
    3. Maximum speed in level flight with maximum continuous power (Vh) of not more than 120 kts (138 mph) CAS under standard atmospheric conditions at sea level.
    Sonex, Waiex, Xenos, and Onex all meet this requirement with their standard propellers for all factory-approved engine installations. ​
    The most common question on these speeds involves the use of the 3300 Jabiru. According to the Jabiru Factory, the maximum continuous power rating of the 3300L Jabiru is 2850 rpm. At this rpm and under the specified conditions, the Sonex and Waiex cruise at 135 mph and the Xenos cruises at 100 mph.​
    [HR][/HR]
     
  4. Apr 3, 2015 #4

    djschwartz

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    Since the aircraft is an E-AB not an E-LSA you can legally use any engine as long as the performance numbers result in an aircraft that conforms to the LSA performance limits. Since the aircraft you're looking at is already completed, you must ensure that the numbers for that specific aircraft, not the numbers published by the designer, meet those requirements. Remember, for an E-AB the builder is the legal manufacturer of the aircraft, not the designer or kit seller. The aircraft should have come with at least a basic POH with performance numbers in it that were what the FAA or designee used to issue the operating limitations and airworthiness certificate. Those are the numbers that must conform to the LSA requirements. It may be that the builder simply copied numbers from the designer as is commonly done for established kit designs; but, the bottom line is still that it is your specific aircraft, not the general design, that must meet the requirements.

    As for the question of changing engines, this becomes a bit more gray. One clause in the FARs states that an aircraft certified in a manner that does not meet the LSA requirements cannot simply be modified to meet them. That is why larger engined and heavier versions of planes like Champs and Luscombes cannot be made sport pilot legal by installing the smaller engine and lowering the maximum gross weight to the number at which the smaller engined version was certified.

    But yours is a E-AB. A change such as a different engine requires the aircraft to undergo a new flight test period and have a new set of operating limitations and airworthiness issued. If you could somehow convince the FAA or a designee that you'd done enough work to meet the 51% rule (which is really a vaguely defined guideline, not a hard and fast rule) then you would have a "new" aircraft and you'd become the manufacturer. But that's unlikely to happen for just an engine change. So you're now left with an aircraft for which you have obtained a new airworthiness and operating limitations that (hopefully) show the aircraft meeting the LSA requirements. Can you fly it with a Sport Pilot License? If the aircraft met the performance limitations before and your new numbers still meet the requirements then I think there is no problem, you can. But by the strictest interpretation of the rules and guidelines, if the original aircraft did not, you're stuck regardless of whether the modified one does. On the other hand, who will really know?

    Also keep in mind that it is up to you to specify what constitutes "Maximum Continuous Cruise Power" for your particular engine and airframe combination. It does not have to be 75% power. The Carbon Cub guys have shown that with their 180 HP "LSA" version of the Carbon Cub.

    Dave
     
  5. Apr 3, 2015 #5

    don january

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    it's all about wing loading is'nt it? Gross wt? guess it dont matter much what motor ya run 1350,1100,950.LB. gross weight for the three type of planes. Out side of those numbers "NO LSA"
     
  6. Apr 3, 2015 #6

    chuckparker

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    Thanks for the replies. Just to be sure I'm understanding tototally. As long as it can be an EAB and flown as an LSA providing it wasn't registered gross weight above 1350 and it's operating limitations don't have speeds listed higher than LSA permits.

    So my best move before traveling across states to look at a plane would be to ask to see the registration and operating limitations. If that checks out then find an A+P to do a prepurchase.
     
  7. Apr 3, 2015 #7

    Dana

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    The operating limitations won't list speeds; they're more of legal restrictions on the operation of the aircraft. There may be (should be) logbook entries recording the performance observed during the initial flight testing, or they may be in the POH if the builder created one. The gross weight, stall speed, and max speed all have to be within the LSA limits.

    Note that you could have a great big engine with a very flat pitch prop which would limit the max speed but still give spectacular climb (probably not applicable to a Sonex).

    Dana
     
  8. Apr 3, 2015 #8

    Aviator168

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    I have a question regarding repairman certificate. Since the original builder hold that certificate. What if he pass away, where do I go to sign it off after service. One thing about eab is that you can repair and sign it off and not to hire expansive ap service
     
  9. Apr 3, 2015 #9

    Dana

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    After maintenance or repairs, even major modifications, anybody can sign it off. Only the annual condition inspection needs to be signed off by the original holder of the repairman certificate or an A&P.

    Dana
     
  10. Apr 4, 2015 #10

    N8053H

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    When it comes to an eab who says one must fill out anything for a repair? The only time anything has to be recorded is during the condition inspection. The rest of the year, one does not have to write anything in any log book. I can replace my mag in my single seat eab and no one has to sign anything or write anything in any book. Its a good idea to log it, but no rule or law says it must be logged. Not in an eab. The only log entry needed is for the condition inspection.

    Tony
     
  11. Apr 4, 2015 #11

    N8053H

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    The airplane in question was built with this engine. If the 40 hrs have been flown off, one does not have to fly these 40 hrs off again. Only after a major change will the FAA make one fly off hrs again.

    The FAA looks at the airframe design. If it meets Sort Pilot or ELSA rules then one does not have a problem, but it is up to the owner builder to make sure the changes made, that it does still meet the rule or Far of SP, ELSA. But who will be aiming a radar gun at you and saying...You are flying 150 mph not 136 mph or whatever SP can fly. I forgot the actual number, I would have to look it up and just don't have that much energy today.
    One can not take an airframe that is known to NOT meet SP, ELSA and expect the FAA to give it an ELSA certificate. Never will happen for the airframe does not meet the rule or FAR from the factory.

    Tony
     
  12. Apr 4, 2015 #12

    skier

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    The LSA weight limit is 1320lbs, not 1350.
     
  13. Apr 4, 2015 #13

    chuckparker

    chuckparker

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    Your right, a typo on my part.
     
  14. Apr 5, 2015 #14

    Richard6

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    I believe that some of the LSA manufactured with the larger engine, say the 3300 Jabaru, the maximum rpm allowed, as stated in the POH, is used to keep the aircraft's speed within the LSA rules.

    In other words, the factory specs the aircraft engine rpm to be no greater then XXX at cruse, even though it is possible for the engine to turn faster rpm.

    Richard
     

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