# AD 75-04-10: Heater Overheat Conditions

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed Martin L-1011-385-1, L-1011-385-1-14 and L-1011-385-1-15
- Effective: February 19, 1975
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-2090
- Registered aircraft: 3 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/983FB6ED8151381F862569750048ABB5.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/75-04-10

## The airworthiness directive

75-04-10 LOCKHEED: Amendment 39-2090. Applies to L-1011-385-1 airplanes certificated in all categories.

Compliance required within 10 calendar days after the effective date of this AD, unless already accomplished.

To prevent heater blanket overheat conditions and possible fires caused by a malfunctioning cargo sump drain heater, Electrofilm P/N 111202-101 (LAC Control No. 672726- 101), accomplish (a) or (b) below:

  (a) Disconnect the C-1, C-2, and C-3 cargo compartment drain heaters per Lockheed Alert Service Bulletin 093-30-A032, dated January 23, 1975, or later FAA-approved revisions, or;

  (b) Equivalent deactivation modifications approved by the Chief, Aircraft Engineering Division, FAA Western Region.

  (c) An airplane may be flown to a base for the performance of the work required by this AD per FAR's 21.197 and 21.199.

  (d) The C-1, C-2 and C-3 cargo compartment drain heaters may be reactivated in accordance with modifications or instructions approved by theChief, Aircraft Engineering Division, FAA Western Region. The approved data must reference this AD, and the FAA-approval date.

This amendment becomes effective February 19, 1975.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A23WE](https://openairdocs.org/tcds/A23WE): Lockheed Martin Corporation; names 3 of 4 models: L-1011-385-1-14, L-1011-385-1, L-1011-385-1-15

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 3 (3 by airframe model, 0 by engine model)
- Makers: Lockheed 3

Models with the most aircraft:

- [Lockheed L-1011-385-1](https://openairdocs.org/model/lockheed-l-1011-385-1): 2 aircraft (airframe model)
- [Lockheed L-1011-385-1-15](https://openairdocs.org/model/lockheed-l-1011-385-1-15): 1 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/75-04-10/models.md
Every aircraft: https://openairdocs.org/ad/75-04-10/aircraft.md

Its text cites no advisory circulars or STCs.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.