Dev Testing of the Spinal Preloading Piston when Integrated into the CKU-5/A Rocket Catapult
Award last edited on: 10/11/05

Sponsored Program
Awarding Agency
Total Award Amount
Award Phase
Solicitation Topic Code
Principal Investigator
Walter Peck

Company Information

LME Inc (AKA: Logistics Management Engineering Inc)

1356 Cape St. Claire Road
Annapolis, MD 21401
   (410) 757-6319
Location: Multiple
Congr. District: 03
County: Anne Arundel

Phase I

Contract Number: F41624-98-C-5049
Start Date: 5/14/98    Completed: 5/14/99
Phase I year
Phase I Amount
Small, light weight, female pilots have been introduced into the AF and Navy pilot population in recent years. The increased spinal loading of light weight ejectees during the catapult stroke, with its attendant increased probability of spinal injusy, that occurs in an ejection is well known. It has also been shown that any upward acceleration of the aircraft during an ejection can appreciably increased the spinal loading with a drastic increase in the probability of spinal injury. Recent studies have shown that a separate short stroke piston that provides preloading of the spine can result in a much reduced spinal loading with some increase in the catapult separation velocity. This proposal is for an eight month study of the possible application of such a spinal preloading piston to the CKU-5/A rocket catapult used in the ACES-II open ejection seat escape system. This study is believed to be critical importance to all AF pilots, and especially to the light weight female pilots, who will be ejecting with the ACES-II ejection seat for many more years into the future.

Phase II

Contract Number: F41624-99-C-6010
Start Date: 3/5/99    Completed: 3/5/01
Phase II year
Phase II Amount
Some level of severity of back injury has occurred in over 50 of 450 ACES ejections. Increased spinal loading of lightweight ejectees during the catapult stroke, which increases the probability of spinal injury, is well researched. Small statured, lightweight, female pilots are now part of the USAF pilot population. Additionally, any upward acceleration of the aircraft during ejection increases the spinal loading causing a drastic increase in the probability of spinal injury. The SBIR Phase I study integrating a Spinal Preload Piston into the CKU-5B/A catapult demonstrated that it will provide greatly improved catapult performance to the ACES II seat for the entire pilot population. The proposed Phase II program defines a test program that will demonstrate the great potential of the preloading concept through the fabrication of test articles, test stand, and assembly of a data acquisition system, culminating in developmental tests. Testing will be representative of the catapult phase of ejections for both lighweight and heavyweight efejctees under both level flight and upward acceleration conditions. This program will bring the AF one stop closer to reducing ejection induced spinal injuries for the entire pilot population.

The proposed test program will provide a solid foundation for the subsequent development/qualification of a spinal preload piston which will improve the ACES-II ejection seat catapult performance for all ejectees, regardless of their weight, and will reduce the probability of spinal injury to all ejectees, especially to the small, light weight, female crewmembers