AD 68-18-04

68-18-04 MCDONNELL DOUGLAS: Amendment 39-649. Applies to all Model DC-8 Series 62 and 63 Airplanes.

Compliance required within the next 35 hours time in service after the effective date of this AD, unless already accomplished.

To eliminate possible intermittent brake release at high ground speed due to anti-skid control box inop light logic card malfunction, either deactivate the anti-skid inop light logic card as follows:

(1) Disconnect wire No. G13AA24 from terminal 18 on terminal strip No. S3-192 and end cap coil and stow, and

(2) Add the following wires:

(a) One routed from terminal board No. S3-192, Terminal 18 to the anti-skid control relay No. R2-300, Terminal A3.

(b) One routed from anti-skid control relay No. R2-300, Terminal A2 to Terminal X2; or

Install a placard stating: "Operation Limitation - Anti-skid inop performance field lengths must be used for all aircraft operations," in view of the pilot, until the modification has been completed.

Reference McDonnell Douglas Wiring Diagram No. 32-3-0. The modification location is in the accessory compartment adjacent to the anti-skid control box. This modification replaces the function of the anti-skid control box inop light logic card by using available contacts on the existing aircraft anti-skid control relay No. R2-300 to accomplish the same function.

This limitation affects only the aircraft operation and does not require that the anti-skid system be made inoperative. The placard limitation may be removed upon completion of the modification described above. (McDonnell Douglas Alert Service Bulletin No. A32-135 DC-8 SC 2090, covers this same modification.)

This amendment becomes effective immediately for all persons except those to whom it was made effective immediately by telegram dated August 22, 1968.