# AD 60-20-04: Lavatory Drains

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed Martin 188A and 188C
- Effective: October 28, 1960
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 4 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0378FB0F33D0E353862569B2006D2A9C.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/60-20-04

## The airworthiness directive

60-20-04 LOCKHEED: Amdt. 203 Part 507 Federal Register September 28, 1960. Applies to 188 Aircraft Serial Numbers 1002, 1004 Through 1102, 1104 Through 1126, and 2001 Through 2015.

Compliance required by the next 300 hours' time in service after October 28, 1960.

Leaking lavatory tank ground drain valves have permitted drainage to the exterior surface of the aircraft in flight, resulting in ice formation which came off and struck the stabilizer. Since such ice formation is hazardous to aircraft in flight and to persons on the ground, all lavatory tank ground drain valves must be modified to incorporate LAC seal No. 838228-1 or equivalent. (LAC 88/SB-407 covers the intent of this change.)

This directive effective October 28, 1960.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4A22](https://openairdocs.org/tcds/4A22): Lockheed Martin Corporation; names 2 of 2 models: 188A, 188C

## 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: 4 (4 by airframe model, 0 by engine model)
- Makers: Lockheed 4

Models with the most aircraft:

- [Lockheed 188C](https://openairdocs.org/model/lockheed-188c): 3 aircraft (airframe model)
- [Lockheed 188A](https://openairdocs.org/model/lockheed-188a): 1 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/60-20-04/models.md
Every aircraft: https://openairdocs.org/ad/60-20-04/aircraft.md

Its text cites no advisory circulars or STCs.

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