# AD 78-13-05: Improperly Installed Seats

- Type: Airworthiness directive
- Status: Current
- Products: Cessna 340, 340A, 402B, 404, 414, 414A, 421, 421A, 421B and 421C
- Effective: July 5, 1978
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-3250
- Registered aircraft: 2,156 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D47530DEF6DD891286256A3400691135.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/78-13-05

## The airworthiness directive

78-13-05 CESSNA: Amendment 39-3250. Applies to the following models and serial number airplanes certificated in all categories:

MODEL SERIAL NUMBERS 340 340-0001 and up 340A 340A0001 through 340A0472 402B 402B0301 through 402B1332 404 404-0001 through 404-0223 414 414-0251 and up 414A 414A0001 through 414A0042 421 421-0001 and up 421A 421A0001 and up 421B 421B0001 and up 421C 421C0001 through 421C0478

COMPLIANCE: Required as indicated unless already accomplished.

To detect seats with seat-to-seat track fittings improperly installed and seats installed facing the wrong direction, which if allowed to go uncorrected, could result in seat failure in those situations where the seats and seat belts are relied on to restrain the passengers, within 25 hours time-in-service after the effective date of this AD accomplish the following:

A) Visually inspect all affected passenger seats for correct installation in the airplane and for proper assembly and correct any discrepancies prior to the next flight, all in accordance with Cessna Multi-Engine Service Letter ME78-17, dated May 15, 1978, or later revisions.

B) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

This amendment becomes effective on July 5, 1978.

## Affected data sheets (3) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A7CE](https://openairdocs.org/tcds/A7CE): Textron Aviation Inc.; names 7 of 16 models: 421C, 402B, 414, 421B, 421A, 421, 414A
- [TCDS 3A25](https://openairdocs.org/tcds/3A25): Textron Aviation Inc.; names 2 of 11 models: 340A, 340
- [TCDS A25CE](https://openairdocs.org/tcds/A25CE): Textron Aviation Inc.; names 1 of 2 models: 404

## 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: 2,156 (2,156 by airframe model, 0 by engine model)
- Makers: Cessna 2,156

Models with the most aircraft:

- [Cessna 340A](https://openairdocs.org/model/cessna-340a): 543 aircraft (airframe model)
- [Cessna 421C](https://openairdocs.org/model/cessna-421c): 496 aircraft (airframe model)
- [Cessna 414A](https://openairdocs.org/model/cessna-414a): 363 aircraft (airframe model)
- [Cessna 414](https://openairdocs.org/model/cessna-414): 242 aircraft (airframe model)
- [Cessna 421B](https://openairdocs.org/model/cessna-421b): 225 aircraft (airframe model)
- [Cessna 340](https://openairdocs.org/model/cessna-340): 164 aircraft (airframe model)
- [Cessna 402B](https://openairdocs.org/model/cessna-402b): 49 aircraft (airframe model)
- [Cessna 421](https://openairdocs.org/model/cessna-421): 28 aircraft (airframe model)
- [Cessna 404](https://openairdocs.org/model/cessna-404): 26 aircraft (airframe model)
- [Cessna 421A](https://openairdocs.org/model/cessna-421a): 20 aircraft (airframe model)

All 12 models: https://openairdocs.org/ad/78-13-05/models.md
Every aircraft: https://openairdocs.org/ad/78-13-05/aircraft.md

Its text cites no advisory circulars or STCs.

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