AD 69-02-03

69-02-03 AVIONS MARCEL DASSAULT: Amendment 39-713. Applies to Fan Jet Falcon Airplanes which have a Collins AP-103E or AP-103F autopilot installed in accordance with Pacific Airmotive Corporation STC No. SA1131WE.

Compliance required as indicated, unless already accomplished.

To prevent possible hazardous in-flight load factors:

A. The following operating limitation is hereby adopted:

"The autopilot shall not be engaged or operated at speeds in excess of 250 knots IAS."

B. Within the next 10 hours time in service after the effective date of this AD unless already accomplished, the operating limitation specified in paragraph A above must be placed in the aircraft in the form of a placard in clear view of the pilot, near the autopilot controller stating:

"The autopilot shall not be engaged or operated at speeds in excess of 250 knots IAS."

C. Remove the placard only upon accomplishment of the modifications described in paragraph E below, or of anequivalent modification approved by the Chief, Aircraft Engineering Division, FAA Western Region.

D. The operating limitation specified in paragraph A above shall not apply if the modifications described in paragraph E below have been accomplished.

E. Modify the Collins AP-103E or AP-103F autopilot system as follow:

1. Replace the elevator primary servo unit Collins P/N 334C-3A with a Collins P/N 334C-3E with the servo torque adjusted to 20.5 plus or minus .2 in-lbs.

2. Check the following:

(a) Aileron and elevator capstan cables for correct seating of ball end fittings into capstan groove.

(b) Aileron and elevator cables for a tension of 65 lbs. plus or minus 5 lbs. If cables are not seated or cannot be tensioned correctly, they should be replaced.

NOTE: Refer to the STC SA1131WE data for rigging instructions.

3. Modify the Dassault aircraft Trim Relay Box M20.632.18, per Dassault Service Bulletin 307, Sec. 1, or later FAA approved revision, or equivalent modification approved by Chief, Aircraft Engineering Division, FAA Western Region.

4. Adjust 161A-1A trim coupler for 8 degrees plus or minus 1 degree per minute trim speed in accordance with the following instructions, or to an equivalent procedure approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(a) Adjust dc ground power to aircraft for 28 vdc (measured at the aircraft bus).

(b) Set the 161A-1A trim coupler potentiometers R2 (up) and R22 (down) to middle of travel.

(c) Engage the autopilot and overpower the elevator servo enough to cause the torque limiting clutch to slip. Adjust R47 to obtain a trim speed of 8 degrees per minute average (check both up and down travel).

(d) Disengage the autopilot and remove servo amplifiers from the 562C-4E computer/amplifier.

(e) Engage the autopilot and apply 540 millivolts dc from external source to test jacks J2 (positive) and J3 in the 161A-1A trim coupler. Adjust R2 to obtain minimum pulsing that actuates the aircraft trim system (up). The time interval between these short pulses should not exceed three seconds.

(f) Remove external source from the 161A-1A trim coupler test jacks J2 and J3 and apply 75 millivolts dc to test jacks J4 (positive) and J5. Adjust R22 to obtain minimum pulsing that actuates the aircraft trim system (down). The time interval between these short pulses should not exceed three seconds.

(g) Recheck trim speed and readjust R47 for 8 degrees plus or minus degree per minute if necessary.

NOTE: Collins Service Information Letter 23-68, dated July 15, 1968, paragraphs 3 thru 6, covers the modification of the AP-103F flight control system only.

This amendment becomes effective on January 25, 1969.