Page:CAB Accident Report, Northeast Airlines Flight 715.pdf/8

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eye fitting Jam locking nut. (Seven inches of inboard actuator extension for a normal flap operation corresponds to 20 degrees of flap extension.)

The hydraulic lines leading to the left and right main landing gear were failed in tension at the main landing gear struts Hydraulic lines through- out the wing flap system were intact with no visible external fluid leakage. The hydraulic system reservoir was checked and the f1u1d measured about l-le inches up on the Sight gauge. This level corresponds to a nearly full system reserv01r. é

The aircraft's flight control system was inSpected and found to be intact and capable of proper operation.

1 13 Fire There was no fire.

1.14 SurVival Aspects

The aircraft did not burn nor was there any major structural breakup on impact or during the ground slide. All of the passengers left the aircraft V13 the main cabin door within an estimated two minutes. The evacuation was orderly and was supervised by the stewardess and the flight engineer. The emergency chute was attached and unfolded, however, because the aircraft was so close to the ground, it could not be utilized as an aid in the aircraft evacuation.

1.15 Tests and Research

The wing flap control valve was functionally tested and found to be in satisfactory operating condition except for slightly excessive internal leakage with the sliding control valve in the neutral position. Howaver, it should be noted that Wlth system pressure being maintained, the flap follow-up linkage would compensate for this leakage by redirecting pressure to the actuator down line thereby maintaining any pre-selected flap position.

The two-speed flap control valve was tested and found capable of proper operation.

Flap extension tests were conducted on the aircraft and it was found that maximum flap extension attained, with the flap selector lever in the full down or 50-degree position, was approximately 44 degrees dDWn.

The pilot and copilot airspeed indicators and altimeters were tested and found to be satisfactory in all respects.

1.16 Supplemental Data The Civil Aeronautics Board was notified of this accident immediately after

occurrence and an investigation was started at once under the proviSions of Title VII of the Federal AViation Act of 1958, as amended. Depositions