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Definition of Motorglider or Powered Sailplane

Sonex Aircraft, LLC accepts the formal definition of Powered Sailplanes for Type Certificated Aircraft from both the United States and the European Aviation Authorities. While it is not formally defined that an Aircraft Registered in the Experimental Category must meet these same criteria, any aircraft which does meet the criteria is an undisputable "Motorglider" or "Powered Sailplane". The language in both the U.S. and the European documents are nearly identical and the portion of the documents which apply to this definition as follows:

United States Department of Transportation, Federal Aviation Administration
Advisory Circular AC 21-17a, dated 10 February 1993

   b. Additional Criteria for Powered Gliders.
    (1) Powered fixed wing gliders may be type certificated under Section 21.17(b) if:
      (i) The number of occupants does not exceed two;
      (ii) Maximum weight does not exceed 850 kg (1874 pounds); and
      (iii) The maximum weight to wing span squared (w/b2) does not exceed 3.0 kg/M2 (0.62 lb./ft.2).
NOTE: These criteria originated from JAR-22.

Joint Aviation Authorities
JAR-22 Amendment 7, dated 1 September 2003

JAR 22.1 Applicability
(a) This JAR-22 prescribes minimum airworthiness standards for the issue of type certificates, and changes to those certificates, for sailplanes and powered sailplanes in the utility U and aerobatic A categories:-
(1)    Sailplanes the maximum weight of which does not exceed 750 kg:
(2)    Single engine (spark- or compression-ignition) powered sailplanes the design value W/b2 (weight to span2) of which is not greater than 3(W[kg], b[m]) and the maximum weight of which does not exceed 850 kg: and
(3)    Sailplanes and powered sailplanes the number of occupants of which does not exceed two.

The following is the applicable data for the Xenos "Motorglider":

            Number of occupants _______ 2
            Maximum Weight __________ 580 kg (1275 pounds)
            Maximum weight to span2____ 3.00 kg/m2 (0.61 lb./ft.2)

Xenos Certification Tips
We asked Joe Norris at EAA, one of the foremost experts on Experimental Aircraft Registration, and he responded with the following. While there is no formal FAA procedure for this, we highly recommend that you follow these steps to ensure your Xenos is registered as a glider:

First, when registering the aircraft make sure to indicate that it is a "glider". This would be done by indicating "glider" where it asks for "class" on the Affidavit of Ownership (FAA Form 8050-88).

Once the aircraft is registered as a "glider", the next step would be to point out to the person doing the airworthiness inspection that you wish to have the aircraft certificated as a "glider". Since there is no way to indicate this on the airworthiness application paperwork, it would be important to indicate this both verbally when talking to the inspector, and also by including a note in your application package indicating that you wish to have "glider" indicated on the airworthiness certificate. This should trigger the inspector to look at FAA Order 8130.2 regarding the listing of "glider" on the experimental airworthiness certificate. This guidance is currently found in Chapter 4, Section 7, paragraph 131d, found on page 128 of Order 8130.2F change 3. The applicant may need to actually point the inspector toward that section, as this may be something the inspector has never been involved with before.

All other application paperwork is filled out the same whether the aircraft is a glider or not. This being the case, it will be up to the applicant to make it clear to the inspector that the aircraft is a glider and should be certificated as such.

Sonex Aircraft also recommends that you fill out your 8050-88 form to read Model: Xenos Motorglider.

Sonex Aircraft also highly recommends that all Sonex, Waiex, and Xenos Builders Purchase the EAA's Amateur-Built Aircraft Certification Kit, which is available for purchase online. The kit includes everything you need to register and certificate a new experimental amateur-built aircraft. The 15- age, step-by-step Certification Guide walks you through the entire process-from getting an N number to the aircraft inspection-and provides samples of how to complete each required form. The certification kit also includes all FAA forms, Experimental sticker (in black), dataplate, and a convenient placard decal sheet.

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