| AD Number | 63-08-01 | Status | Active |
| Effective Date | April 09, 1963 | Issue Date | Not specified |
| Docket Number | Unknown | Amendment | N/A |
| Product Type | ["Aircraft"] | Product Subtype | ["Small Airplane"] |
| CFR Part | --- - Part 39 | CFR Section | N/A |
| Citation | This information is not available. | ||
| Manufacturer(s) | Twin Commander Aircraft LLC |
| Model(s) | 520 |
63-08-01 AERO COMMANDER: Amdt. 552 Part 507 Federal Register April 9, 1963. Applies to Model 520 Serial Numbers 1 Through 130 With the Fuel Gaging System Having the Dual Needle Quantity Indicator Installed.
Compliance required as indicated.
There have been cases of fuel exhaustion inflight while the fuel quantity indicators indicated adequate fuel remained in the fuel system. It has been determined that in some cases, the fuel quantity indicator needles stick in one position while fuel continues to be consumed. In other cases, it has been determined that the transmitters have become worn or inoperative resulting in inaccurate indications of fuel quantity.
To preclude malfunctions and misinterpretations of the gaging system, within the next 100 hours' time in service after the effective date of this AD comply with the requirements set forth in paragraphs (a), (b), (c) and (d) or replace the system in accordance with paragraph (e).
(a) Inspect the fuel quantityindicator and repair or replace as necessary, to render the indicator airworthy.
(b) Inspect both transmitter units and repair or replace as necessary to render the units airworthy.
(c) Inspect transmitter float travel and recalibrate the gaging system in accordance with Aero Commander Service Letter 97 dated May 12, 1961. Repeat within each 300 hours' time in service after the initial inspection and calibration.
NOTE: When reinstalling vapor box cover (item k of Aero Commander Service Letter 97) dip the grip of the screws with Minnesota Mining and Manufacturing compound EC-750 or equivalent. Also, seal the access covers (items 1 of Aero Commander Service Letter 97) with the same sealant upon reinstalling the access covers.
(d) Attach the following placard to the instrument panel below the fuel quantity indicator:
CAUTION
0 to 20 Scale Measures Only That Usable Fuel Between 0 and 20 Gallons in the Tank.
0 to 110 Scale Measures Only That Usable FuelAbove 20 and Below 130 Gallons in the Tank.
Add Readings To Obtain Total Quantity up to 130 Gallons. Confirm Quantity Above 130 Gallons by Inspecting Tank Prior to Flight.
(e) Unless already accomplished, remove the existing dual transmitter and dual needle indicator gaging system and install a new improved gaging system in accordance with Aero Commander Service Change 27 dated October 27, 1954, reissued March 30, 1961, or an FAA Engineering and Manufacturing Branch approved equivalent. If the new improved gaging system is installed subsequent to the accomplishment of (a), (b), (c) and (d), the repetitive inspections required by (c) may be discontinued and the placard required by (d) may be removed.
This directive effective April 9, 1963.