# AD 47-20-08: Battery box drain

- Type: Airworthiness directive
- Status: Current
- Products: Univair 415-C, 415-CD and 415-D
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Registered aircraft: 1,005 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0E2BBE76665A1B9D86256A4D005DE91E.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-20-08

## The airworthiness directive

47-20-08 ERCO: (Was Mandatory Note 16 of AD-718-6.) Applies to 415-C, -CD and -D Aircraft. Compliance required prior to July 1, 1947. (a) Install a new battery box drain tube to extend at least 1/2 inch below the fuselage belly skin if this has not been already incorporated in the airplane. (b) Examine the fuselage structure and controls carefully for corrosion. If corrosion is found on the structure, the affected areas should be washed with an alkaline solution and followed by a thorough clear water rinse. Corroded controls should be replaced. (c) Examine the baggage compartment for deterioration. If damage is evident, wash the affected area with a diluted alkaline solution and rinse with clear water. Reinforce any damaged areas with 10 1/2-ounce single filled water-resistant canvas, double sewn with 16-4 glace finished thread. (d) Install decalcomania (Erco P/N 415-54062) on the top of the battery box cover. (Ercoupe Service Department Memorandum No. 44 dated February 17, 1947, and Ercoupe Service Department Bulletins No. 8 dated May 24, 1946, and No. 22, dated February 3, 1947, also cover the above subjects.)

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-718](https://openairdocs.org/tcds/A-718): Univair Aircraft Corporation; names 2 of 2 models: 415-CD, 415-C
- [TCDS A-787](https://openairdocs.org/tcds/A-787): Univair Aircraft Corporation; names 1 of 8 models: 415-D

## 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: 1,005 (1,005 by airframe model, 0 by engine model)
- Makers: Ercoupe 772, Engineering & Research 200, Forney 20, Erco 12, Univair 1

Models with the most aircraft:

- [Ercoupe 415-C](https://openairdocs.org/model/ercoupe-415-c): 623 aircraft (airframe model)
- [Engineering & Research 415-C](https://openairdocs.org/model/engineering-research-415-c): 160 aircraft (airframe model)
- [Ercoupe 415-D](https://openairdocs.org/model/ercoupe-415-d): 101 aircraft (airframe model)
- [Ercoupe 415-CD](https://openairdocs.org/model/ercoupe-415-cd): 48 aircraft (airframe model)
- [Engineering & Research 415-D](https://openairdocs.org/model/engineering-research-415-d): 24 aircraft (airframe model)
- [Forney 415-C](https://openairdocs.org/model/forney-415-c): 17 aircraft (airframe model)
- [Engineering & Research 415-CD](https://openairdocs.org/model/engineering-research-415-cd): 16 aircraft (airframe model)
- [Erco 415-C](https://openairdocs.org/model/erco-415-c): 7 aircraft (airframe model)
- [Erco 415-D](https://openairdocs.org/model/erco-415-d): 4 aircraft (airframe model)
- [Forney 415-D](https://openairdocs.org/model/forney-415-d): 2 aircraft (airframe model)
- [Forney 415-CD](https://openairdocs.org/model/forney-415-cd): 1 aircraft (airframe model)
- [Erco 415-CD](https://openairdocs.org/model/erco-415-cd): 1 aircraft (airframe model)
- [Univair 415-D](https://openairdocs.org/model/univair-415-d): 1 aircraft (airframe model)

All 13 models: https://openairdocs.org/ad/47-20-08/models.md
Every aircraft: https://openairdocs.org/ad/47-20-08/aircraft.md

Its text cites no advisory circulars or STCs.

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