On 17 July, 1997 M/s Rawalpindi Flying Club Cessna 152 aircraft Reg.No. AP-BAW executed a forced landing near Mandra due to loss of engine power. While flying a Navigation mission satisfactorily for about 50 minutes the student pilot observed severe engine RPM fluctuation at a height of about 4500 feet. On taking over the controls the instructor Pilot selected carburator Heat System and moved the power lever to and fro several times but the situation didn't improve. Realising that aircraft was contineously loosing height a forced landing was executed safely on a rough ploughed field. No injury to any person or damage to property was caused to the aircraft or any life or property.