Indonesia Air Force Lockheed Hercules C130 Air Crash Investigation Preliminary Report

What We Know ?

1. Lockheed Hercules C-130 aged over 50 years (built in 1960's) used for transporting military personnel and their families.

2. Person on board, 12 crews and 109 passengers took off from Soewondo Air Base noon local time 12:08 (+7 UTC).Scheduled to Tanjung Pinang, Natuna, pontianak before retuning to Malang.

3. Minutes after take off, pilot in command requested permission to return to base.

4. The plane banked (intentionally to return or effect from the failure engine) to the starboard (right) before meets the ground,bursting into flames and wiping out the building (hotel).

5. There are no Flight Data Recorder (FDR) and Cockpit Voice Recorder (CVR) attached to the plane.

Preliminary Cause Explaination 



6. The accident happens two minutes after take off, that's means there is no sufficient lift force to sustain the flight.Aerodynamic stall maybe the suspect.

7. Aerodynamics stall normally happens due to contamination on the wings or there is not enough power for the wings to apply bernoulli's theorem to lift the plane.

8. When running for take off, full throttle applied to achieve ideal lift speed (VR speed).Malfunction or not enough power should be the cause.Prime suspect for insufficient power to lift the plane are both engines.

9. The plane did lifted,  but cannot attain the climbing behaviour. The engine/s flame out after VR. VR speed achieved but cannot maintain power.

10. From these criteria, the plane experiencing engine failure after take off before plumed to the ground.

11. If the plane tends to bank to the right before crashed to the ground. Suggesting only a engine flame out and the left engine (engine no. 1) still functioning at the time.

12. If the pilots intentionally turn the plane banked to the right maybe both engines flamed out.

13. With the engines flame out, there is no thrust generated, in result, there is no lift generated. Therefore, any turn or maneuver which produces drag will compensate the lift left.Plus the amount of fuel will increasing the ability of the plane to going down faster than small amount fuel on board.

14. Lift generated by the engines gradually decreasing but the drag force increasing results from turn will force the plane slammed the ground. Short distance and altitude does not give the plane to glide safely to the intended crash landing site.

Aftermath

15. More than 140 recovered,on board or on the ground.