David M. McDonald

VP Operations

7765 Northwest 54th Street 

Miami, Florida 33166 U.S.A. 

Phone 305.594.5802

Fax 305.594.5804

www.aeronautical-engineers.com

dmm@aeronautical-engineers.com

May 16, 2012 

U.S. Department of Transportation 

Docket Management System 

400 7th Street SW 

Room PL 401 

Washington, DC 20591-0001 

Attention Transport Airplane Directorate 

 RE: Request For Exemption From FAR §25.785(k) For Freighter Aircraft 

 (STC # ST01827LA) 

To Whom It May Concern, 

Aeronautical Engineers, Inc. (AEI) has been granted an exemption from certain Federal Aviation 

Regulations (FAR) pursuant to 14 CFR Part 11, via Exemption No. 9722, allowing the carriage of 

up to 4 non-crewmembers (commonly referred to as supernumeraries). In addition to the 

exemptions requested and granted in Exemption 9722, AEI also seeks an exemption from the 

requirements of FAR §25.785(k) 

The petitioner requests relief from the following regulations: 

§25.785(k), Amendment 25-88, requires (k) Each projecting object that would injure persons 

seated or moving about the airplane in normal flight must be padded. 

The petitioner supports its request with the following information: 

AEI holds numerous Supplemental Type Certificates for modification of transport aircraft. With 

regard to this petition, AEI holds STC ST01827LA which allows conversion of Boeing 737-

300/400 aircraft to a freighter with a Class E main deck cargo compartment. Over 200 Boeing 

aircraft have been converted by AEI to freighters. Some operators of AEI freighters need to be able 

to carry supernumeraries to assist with special cargo such a valuable cargo requiring security 

and/or perishable, fragile, or live cargo requiring special attention to ensure its safe delivery. The 

interest of the petitioner is in providing a level of safety for the crew, supernumeraries, cargo and 

aircraft that will allow operators of AEI converted 737 freighters to meet the needs of their 

clientele. 

In this case, the supernumeraries are limited to a maximum of 4 persons. There are far fewer 

supernumeraries on a freighter than passengers on a passenger aircraft. The supernumeraries, 

unlike passengers, will be trained on emergency procedures, including emergency egress and 

safety during flight. The area available for the supernumeraries is very limited and the 
David M. McDonald

VP Operations

7765 Northwest 54th Street 

Miami, Florida 33166 U.S.A. 

Phone 305.594.5802

Fax 305.594.5804

www.aeronautical-engineers.com

dmm@aeronautical-engineers.com

supernumeraries will normally be seated in the flight attendant (F/A) seats during flight, except to 

use the lavatory or galley. See included photos and diagram below. 

AEI B737-300/400 Freighter Supernumerary Area 

The emergency equipment, the cargo door control panel and cargo door hydraulic system panel are 

installed on the 9G barrier adjacent to the F/A seats. These objects do not pose a hazard to the 

supernumeraries when seated and will not be a hazard during normal flight. As shown in the 

diagram above, this is a very small area and, when not in their seats, supernumeraries can easily 

steady themselves with the surrounding aircraft structure. 
David M. McDonald

VP Operations

7765 Northwest 54th Street 

Miami, Florida 33166 U.S.A. 

Phone 305.594.5802

Fax 305.594.5804

www.aeronautical-engineers.com

dmm@aeronautical-engineers.com

9G Barrier and Forward Facing Supernumerary Seat 
David M. McDonald

VP Operations

7765 Northwest 54th Street 

Miami, Florida 33166 U.S.A. 

Phone 305.594.5802

Fax 305.594.5804

www.aeronautical-engineers.com

dmm@aeronautical-engineers.com

Retained Original F/A Seat 

Request for Waiver of Public Comment

AEI requests waiver of the normal public comment process since this request is substantially 

similar to those already granted to other freighter STC holders and because the granting of this 

petition will not create new precedent. 

2. Public Interest 

The carriage of an appropriate number of attendants aboard an aircraft to monitor and to attend to 

the special requirements of valuable, fragile, perishable, or live animal cargo, serves the public 
David M. McDonald

VP Operations

7765 Northwest 54th Street 

Miami, Florida 33166 U.S.A. 

Phone 305.594.5802

Fax 305.594.5804

www.aeronautical-engineers.com

dmm@aeronautical-engineers.com

interest in raising the level of safety of the cargo, the airplane, the flight crew, and consequently, 

the public in general. In addition, these exemptions will enhance the utility of the aircraft, thereby 

helping to reduce shipping costs, which will in turn be in the public interest. 

This exemption, therefore serves the public interest for safety reasons and also for increased 

airfreight utility, both domestically and internationally and consistent commercial operations 

among all AEI freighter operators. 

AEI respectfully requests that this petition be granted. 

Sincerely, 

David M. McDonald, 

Vice President