Originally Posted by
kmcbrid2
I want to make sure I understand this. When you say survivable accident, are you talking about a crash/hard landing?
I can envision how a lap belt protects a lap child from turbulence (and why I feel comfortable flying on international carries who require lap belts) but I can't grasp how a lap belt could injure a lap child? The only thing I can envision is if the plane suddenly stops during take-off or landing causing a parent to fold over on a lap child being held by a lap belt.
I haven't found any facts to back up my assumption but I would think these events would be far less likely than the 33 injuries due to turbulence? If anyone has these facts please share.
Hi kmcbrid2...
You are correct in that my reference to a survivable accident can be taken as meaning a "crash" - essentially, an event that typically results in some measure of structural damage to the aircraft.
You second statement is also correct. While not perfect, most aviation regulatory authorities have elected to require the use of the loop belt as it provides a level of protection during normal or abnormal operations and periods of in-flight turbulence not afforded to an unrestrained infant. In the event of an accident, neither the loop belt nor unrestrained lap infant is ideal, for many reasons. In relation to the loop belt specifically, a number of studies have been conducted to evaluate its effectiveness in an accident. Although a worst-case scenario, the following reports summarize the primary hazard associated with its use:
"In a suddenly occurring deceleration in the longitudinal aircraft axis, the adult and the infant show a pronounced jack-knife effect. The upper torso and the lower extremities of the infant as well as of the adult sitting behind the infant fold up in a forward direction, with the loop belt restraining the infant. Finally, the loop belt drives into the infant's abdomen and only stops at his or her vertebral spine. From the technical point of view, the infant acts like an energy absorption element for the adult; the crash loads acting on the adult are thus reduced, and the infant fixed with the loop belt thus suffers most serious up to fatal injuries."
Examination on the Enhancement of Cabin Safety for Infants
"The data and observations from the four tests with the belly belt did not produce any favorable results. The impossibility of protecting a small child, by any means, sitting on the lap of an adult restrained by seat belts was confirmed in these tests. Severe contact with the forward row seat back was observed during double row tests. The recorded head impact of the 6-month old CRABI ATD resulted in a HIC above 1900. Abdominal pressures from the CAMIX ATD were 50% greater than data from booster seats under similar conditions. Aft row occupant impact on the breakover seat back resulted in a definitive peak in the abdominal pressure data. Based on the biomechanical data as well as observations of the films from these tests, the belly belt should not be construed as means of protecting small children."
The Performance of Child Restraint Devices in Transport Airplane Passenger Seats
A couple of sources of additional accident information and statistics would be the following:
Boeing: Statistical Summary of Commercial Jet Airplane Accidents - Worldwide Operations - 1959 - 2011
Aviation Safety Network