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Safety Research That Gathers Dust On Bookshelves Not Helpful

On Behalf of | Feb 22, 2022 | Accidents & Incidents, Articles, Briefs, Regulatory & Other Items

For a highly pertinent example of the Federal Aviation Administration (FAA) not following-up on its own research, look no further than its requirements for life preservers. I use life preservers as my prime example because, unlike avionics and other esoteric electro-mechanicals of airplanes, most people understand the problem of floating for extended periods in cold water.

Cold water is the key. Water saps the body’s heat at a much faster rate than cold air. With the body numb from cold, muscle coordination atrophies, the mind loses concentration – the will to live is sapped much quicker. In cold water, even if one’s head is kept above the waves, one can die from the cold even if the airway is free to breathe. And remember, many survivors of a ditching may be suffering from shock and trauma even before they grab a flotation aid and evacuate the sinking airliner. These people are doubly vulnerable to the effects of cold water.

Every seat cushion and life preserver on an airplane used for flotation must conform to the FAA’s Technical Standard Order, in this case TSO-C13f, issued in 1992, dealing with life preservers.

The TSO covers a great deal about the required preserver performance. Herewith, selected passages:

“This technical standard order (TSO) prescribes the minimum performance standards [emphasis added] that life preservers must meet …”

“This standard covers inflatable (Type I) and noninflatable (Type II) life preservers. Both Type I and Type II preservers are divided into the following four categories: Adult, Adult-Child, Child, and Infant-Small Child.”

“For coated fabrics used in the manufacture of inflation chambers, the maximum permeability to helium may not exceed 5 liters/square meter in 24 hours at 77 degrees F or its equivalent using hydrogen.”

“The force necessary to operate the mechanical inflation means may not exceed 15 pounds when applied through the pull cord.”

“(A)t least 75% of the total number of test subjects … can don the life preserver within 25 seconds unassisted, starting with the life preserver in its storage package …”

“After donning, inadvertent release by the wearer is not likely.”

The TSO lists the required color of the vest (international orange-yellow), the readability of instructions (a minimum viewing distance of 24 inches with illumination no greater than 0.05 foot-candle), and material properties (separation rate must be 2.0 to 2.5 inches/minute). Buoyancy, survivor locator light performance, and salt-spray standards are laid out in detail. Oh, and the preserver must be comfortable to wear in the water.

The TSO is absolutely silent on a critical matter: its aid in heat retention in cold water. A 1985 report by the FAA’s Civil Aeromedical Institute (Report No. DOT/FAA-AM-85-11) on the development of a better life preserver noted:

“If a life preserver provides a measure of thermal protection, not only are the chances of death caused by hypothermia decreased, but also the chances of death caused by drowning decrease.”

Citing a number of accidents where aircraft crashed into cold water, the FAA required research into a preserver that would not only keep the person afloat but would also “provide increased thermal protection in the event of accidental submersion in cold water.” This requirement was in addition to a donning time of 15 seconds, and all the buoyancy, marking and storage requirements of the existing TSO.

During water immersion, the body loses heat at about 26 times the rate it does in air. A close fitting life preserver was designed to minimize degradation of the body’s core temperature in the upper torso (most heat is lost from the trunk, not the limbs).

Test subjects, outfitted with rectal thermometers, were required to wear a prototype preserver in cold water, and a trial was also conducted with the standard life preserver found on airliners today. Pages and pages of graphs show that the prototype preserver retained about 50%-60% more body heat.

Based on rectal temperatures of subjects in 55 degree water, the report concluded:

“(T)he mean estimated predicted survival time was greater for subjects wearing the prototype life preserver than when the same subjects wore the standard PFD [personal flotation device].”

Note, this prototype preserver met all the other requirements for storage (in the same space), for buoyancy (35 pounds), for ease of donning (about 18 seconds), and so forth.

Note also that the improved life preserver report was produced in 1985, a good seven years before publication of the current TSO. Even the FAA apparently has forgotten about this report and its life-saving findings. It had no effect on the TSO or any other FAA requirements for life preserver effectiveness.

Basically, passengers today rely on either the seat cushion, with absolutely no thermal protection, or an obsolescent preserver that was not designed with heat retention as a basic function.

The improved design could be produced at about the same cost. Why was it not pushed by the FAA? One suspects industry resistance at the total cost – which could be absorbed through a multi-year program of fielding the improved model, estimated to cost about $35 apiece.

This is not the only case where the FAA has developed something that enhances safety that does not find its way into the airline fleet. In 1979 the FAA Technical Center published a report on its successful fuel tank inerting system. This 600-pound system displaced explosive fuel-air gasses in fuel tanks with inert nitrogen enriched air. The technology was tested in an FAA DC-9 airliner and passed all performance criteria with flying colors. The weight of the inerting system, we should note, was comparable to or less than the weight of many in-flight entertainment systems, which the airlines have aggressively deployed.

The FAA never mandated that this inerting system be installed on airliners. In 1996, TWA Flight 800, a B747, blew up when volatile vapors exploded in the plane’s center fuel tank. Now the FAA has ordered a less-capable inerting technology to be installed in all but the oldest airliners, and to get the job done by 2018 – fully 22 years after TWA 800 exploded. (See Aviation Safety Journal, August 2008, ‘Significant Regulatory & Related Activity’)

In light of all this, a couple pertinent questions arise. First, why does the FAA bother to explore new technologies or equipment if the results of its efforts just gather dust in obscure reports? Millions of dollars could be saved by closing down the Civil Aeromedical Institute and the Technical Center. This writer cannot think of a single technology or improvement that has been adopted as a result of the work at these subordinate agencies.

Second, if the Civil Aeromedical Institute and the Technical Center are going to be retained, and they continue to develop useful devices and techniques for the safety of the industry, there is an obviously related and relevant question: why isn’t there a link between the FAA’s development efforts and FAA requirements for implementation or adoption by the airline industry?

There is no evident linkage. In an FAA that touts safety as Job #1, advances to safety developed by the agency’s most committed and best minds seems to languish somewhere around Job #0.