58-05-03 VICKERS: Applies to All Viscount 700 Series Aircraft.
Compliance required as indicated.
In accordance with the British Air Registration Board's list of "Essential Modifications and Inspections", compliance with the following Vickers-Armstrong corrective measures is considered mandatory. The FAA concurs and considers compliance therewith mandatory. Compliance provisions are detailed in the Vickers publications referenced in each item.
A. MODIFICATION ELEVATOR AND RUDDER CONTROL LOCKS.
To insure freedom of movement over the complete range of travel of the gust lock lever, install special shoulder greaser bolts in accordance with Mod. D.1421 to prevent over-tightening of the nut securing the lock lever. Also, on elevator gust lock unit P/N A.1949-1 chamfer the sides of the slotted recess in accordance with TNS No. 64, issue 2. Compliance required by April 15, 1958.
B. CONNECTION OF A.C. PHASE TRANSFORMER.
Mod. D.1677 revises the electrical circuit, placing transformers on the input side of the circuit breakers to prevent feed back through the primary of A.C. phases transformers. (This is further to Mod. D.1513.) Compliance required by April 15, 1958.
C. REDISTRIBUTION OF BUS-BAR SUPPLIES TO PITOT HEAD HEATERS.
By supplying the heaters from different bus-bars, complete loss of pitot-head deicing due to failure of one bus-bar is prevented. Mod. D.2019 covers this subject. Compliance required by September 15, 1958.
D. INSPECTION AND MODIFICATION OF ELEVATOR ANTI-BALANCE TAB MECHANISM.
To prevent over-center jamming of the elevator anti-balance tab mechanism, PTL No. 160 prescribes precautionary checks of the tab mechanism maximum travel as well as modifying the link. (PTL No. 160 and Mod. D.2239 cover this subject.) Compliance required by April 15, 1958.
E. IMPROVE THE LOCKING OF THE FORWARD ELEVATOR AND AILERON LEVER GROUP AT COCKPIT STATION 53 AND AILERON LEVER GROUP AT FUSELAGE STATION 462.68.
To prevent lost movement in the aileron control system and possible loosening of the aileron bellcrank level, Mod. D.2091 introduces new fittings and attachment means. Compliance with PTL No. 141 or Mod. D.2091 required by April 15, 1958.
F. INCREASE CUT-OUT IN PILOTS FLOOR FOR ELEVATOR CONTROL CLEARANCE.
Mod. D.2120 increases size of cutaway in pilots floor area to eliminate fouling of elevator rod attachment bolt when incorrectly assembled. Compliance with PTL No. 140 or Mod. D.2120 required by July 15, 1958.
G. FAIRLEADS FOR ELEVATOR TRIM TAB CHAIN AT FRAME STATION 783.
In order to preclude jamming of the elevator trim tab chain where it passes through the frame Station 783, a fairlead Vickers drawing No. 70152, P/N's 1205, 1207, and 1209, should be installed at the cutaway in the frame in accordance with Vickers Mod. D.1602. Compliance required by April 15, 1958.
H. INSPECTION OF TYPE S.1, S.2 AND S.4 RELAYS.
To prevent shorting of relays due to loosening ofthe securing screws on the armature springs PTL No. 147 specifies inspection for security and locking of the shakeproof lock washers and to further lock by the application of either Glyptal Varnish CS.184 or Bakelite Varnish V.130. Compliance required by April 15, 1959.