14 DISC
Design and development of Canopy Lift Check Device in Fighter aircraft
1. As per the existing maintenance procedure of canopy lift check, the lift of canopy bubble is measured using the conventional graph papers fixed on the canopy front and rear glass and canopy frame (06 points on each side).
2. The measurement of lift is by visual inspection of the graph paper on the reference marked before the canopy pressurised and after pressurisation this canopy lift is visually checked at each points on the graph. In case of deviation of 1.5 mm from the previous value at any location in canopy is observed, it is declared unserviceable.
3. This visual inspection of deviation (Lift) value is prone to parallax error. Also, the least count of graph paper is 1mm. Hence, to avoid the chances of error and to have more accurate reading, a sensor based system with high precision is required.
4. Design, development, testing and certification of suitable sensor based device having capability to detect and measure the canopy lift upon pressurisation at multiple location (at least twelve points simultaneously) on the canopy gIass with up to 0.1 mm as least count (least count of 0.01 mm is desirable). This will help in monitoring the canopy lift very precisely and there will be no chance of parallax error. It should have: -
4.1 Facility to visually depict canopy lift i.e. if within limits then Green colour and if not within limit then Red colour at each measuring point.
4.2 Device installation and its operation should be user friendly.
4.3 Device mounting and measurement system should not cause any abrasions/scratches/damage to canopy bubble as well as canopy/aircraft surface.
4.4 The system should have facility to store at least twenty previous recordings of the lift check, aircraft wise, in order to depict the trend of the lift check.
4.5 Sensor should be designed in manner that. It can be mounted on the aircraft frame or kept near the aircra
