FAA seeks comments on Fedex plan to modify A321-200 to add infrareds
Civilian aircraft have been fired upon by man-portable air defense systems in several incidents over recent years.
The Federal Aviation Administration (FAA) has invited comments on the proposed special conditions for the Airbus A321-200 to be modified by FedEx Express (FedEx), which includes a design feature that emits infrared laser energy outside the aircraft as a countermeasure against heat seeking missiles.
"The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature," says FAA in its public notice inviting comments. "These proposed special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards."
Comments have been sought till March 4, 2022 under Docket No: FAA-2021-0775.
Story till now
Fedex had, on October 16, 2019, applied for a supplemental type certificate (STC) to install a laser-based missile-defense system, which directs infrared laser energy toward heat seeking missiles on the Airbus A321-200 aircraft.
"This airplane, which is a derivative of the Airbus Model A321 series airplanes currently approved under Type Certificate No. A28NM, is a twin-engine, transport-category jet with allowable seating for 220 passengers, and a maximum takeoff weight of 89,000 pounds."
Civilian aircraft have been fired upon by man-portable air defense systems (MANPADS) in several incidents abroad over recent years. "This has led several companies to design and adapt systems like a laser-based missile-defense system for installation on civilian aircraft to protect those aircraft against heat-seeking missiles.
"The FedEx missile-defense system directs infrared laser energy toward an incoming missile, in an effort to interrupt the missile's tracking of the aircraft's heat."
Now, the concerns:
* Infrared laser energy can pose hazard to persons on the aircraft, on the ground, and on other aircraft.
* The risk is heightened because infrared light is invisible to the human eye.
* Human exposure to infrared laser energy can result in eye and skin damage, and affect a flight crew's ability to control the aircraft.
* Infrared laser energy also can affect other aircraft, whether airborne or on the ground, and property, such as fuel trucks and airport equipment, in a manner that adversely affects aviation safety.
The FAA has admitted that its standards for transport category aeroplanes did not envisage that a design feature could project infrared laser energy outside the aircraft. "The FAA's design standards are inadequate to address this capability. Therefore, this system is a novel or unusual design feature, and the FAA has developed the proposed special conditions to establish a level of safety equivalent to that of the regulations."
Proposed plan of action
The FAA has proposed the following measures for the installation of the missile-defense system:
"Condition 1 requires the design to have means to prevent inadvertent operation of the system while the aeroplane is on the ground, including during maintenance. These modes must include errors in aeroplane maintenance and operating procedures such as erroneously setting the system to air mode while the aeroplane is on the ground. The applicant could show such failure modes, their risks, and how they will be addressed, by conducting safety assessments and incorporating prevention strategies into the design."
"Condition 2 requires that the system be designed so that in-flight operation does not result in damage to the aeroplane or to other aircraft or injury to any person. To account for these effects, the applicant's analysis should include effects from the system's erroneous operation, system failures, and failures that may not be readily detectable prior to flight (i.e. latent failures). The applicant may address this condition through safety assessments and incorporation of prevention strategies into its design."
Markings, instructions, and other information
"Conditions 3, 4, and 5 are intended to protect certain categories of persons based upon their expected interaction with the system. These conditions require the design to supply certain safety information to these persons."
After considering public comment, the FAA can impose these special conditions on Fedex, and issue a STC for the installation of the system, FAA said in its notice. "Such approvals would not constitute approval to operate the system. FAA Advisory Circular 70-1, "Outdoor Laser Operations," provides guidance on obtaining operational approval."
The FAA has made it clear that these proposed special conditions are applicable to the Airbus A321-200 as proposed to be modified by FedEx. "Should FedEx apply at a later date for a supplemental type certificate to modify any other model included on Type Certificate No. A28NM to incorporate the same novel or unusual design feature, these special conditions would apply to that model as well.