Project: Airbag Restraint for Motorcycles

Reference: S101D/VD

Last update: 12/12/2003 09:25:29


To evaluate the efficacy of an airbag system on motorcycles in reducing the potential for fatal and serious head and chest injuries.


The majority, about 80%, of motorcycle fatalities are from head injuries and the other 20% are largely from chest injuries; many of the serious injuries are also to the head and chest. The Vehicle Standards and Engineering (VSE) Division of the Department of Transport contracted the Transport Research Laboratory (TRL) to investigate means of improving motorcycle secondary safety and this is the final report of the research to evaluate the use of an airbag system on motorcycles designed to reduce the potential for fatal and serious head and chest injuries.

It is known that fatal and serious head injuries tend to occur in impacts where the motorcycle is at approximately 90 to the target (usually a car) and that the majority of impacts (about 75%) occur at an impact speed for the motorcycle of 48 km/h or less with the car travelling slowly (typically 16 km/h or less). Therefore, the system was designed to have optimum performance in an impact with the motorcycle travelling about 48 km/h into the side of a stationary car. The main objectives for the performance in this impact configuration were that the kinetic energy of the rider should be reduced by at least 75% (measured at the plane of impact) and the potential for fatal and serious head and neck injuries should be substantially reduced. It was also required that the system be generally of some benefit in oblique impacts and that 'due care' must be taken for prone and pillion riders.

To achieve these objectives the research was divided into six main phases as follows:

* analysis of existing data;
* computer simulation;
* system design and construction;
* static fire tests;
* sled tests; and
* full scale impact tests.

The predictions of note from the analysis of existing data, based mainly upon trajectory analysis and head and chest acceleration measurements, were that the airbag capacity should be about 90 litres and placed in the rear of the fuel tank, the most suitable inflator was a hybrid (gas with chemical charge) and that the objectives as described above could be readily achieved.

After assembly of the system into the motorcycle frame, the airbag was evaluated in a series of static deployment tests (Phase IV) to assess and develop the inflation time and rate, airbag shape and size, airbag folding pattern, housing arrangement, system cover, rider interaction with the deployed airbag and the temperatures generated by the system.

Phase V was the assessment of the chosen air-bag system performance on TRL's dynamic sled facility. This comprised over 30 tests many of which were part of the procedure to determine the correct pulse to represent different impact configurations and 14 tests to assess the airbag performance over a wide range of conditions in addition to the 48 km/h 90o impact for which the performance was optimised.


TRL Limited
Crowthorne House, Nine Mile Ride, Wokingham, Berkshire, RG40 3GA
+44 (0)1344 773131

Contract details

Cost to the Department: £2,743,630.00

Actual start date: 01 March 1992

Actual completion date: 31 December 1997


Paper. Airbag Restraint for Motorcycles. ESV conference Melbourne 1996
Author: TRL Ltd
Publication date: 01/03/1996
Source: Contact