Pyrotechnical thrustor PL 91


In-flight vibratory analysis of aircraft structures, carried out by means of impulse excitation applied through thrustors, offers positive advantages compared with other processes :
              * Reduced testing time
              * Small size
              * Simple application

The PL 91 thrustor is a new model of simple design and of reliable and reproductible operation, allowing the synchronization of several thrustors controlled simultaneously.

It is composed of a rectangular bar made of a block of hollowed-out aluminium, equipped at one end with the firing relay (black powder plus firing tube), and at the other end with the ejection nozzle for the gases, mounted perpendicular to the top face, including its security device.

The principal charge consists of propergol strips whose length and thickness are calculated to suit the desired force and combustion time.

The thrust time curve is similar to a "square wave" impulse.

The PL 91 thrustor meets the standard operating specifications and the particular ambient conditions for in-flight tests -(temperature, vibration, shock, pressure, etc...).

Conventional thrust

180 daN

Charge, delivered with cable 50 cm

1,6 g black powder
20 g propergol for e = 0.67 mm

Conventional combustion time, depending on the thickness of the propergol strips

12 ms
18 ms
22 ms
26 ms

Dispersion over firing period

4 ms

Frequency range depending on the thickness of the propergol strips

30-70 Hz
20-50 Hz
10-40 Hz
   5-30 Hz

Ohmic resistance

2 0,4 Ohm

Minimum operating intensity

0.35 A

Recommended ignition intensity

> 2.5 A

Safety and measurement intensity

< 0.05 A


500 g

Overall dimensions (mm)

172 x 35 x 35

Fixing points

4 holes M 4 diameter,
spacings 140 x 28

Operating and storage temperature

- 40C + 70C

Flash point


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