# AD 68-08-07: Airspeed and Altimeter Systems

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed Martin 1329-23A, 1329-23D and 1329-23E
- Effective: April 19, 1968
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-585
- Registered aircraft: 1 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0C9493BDEF270FA28625697500489BD7.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/68-08-07

## The airworthiness directive

68-08-07 LOCKHEED: Amendment 39-585. Applies to Model 1329 Airplanes, Serial Numbers 5001 through 5092, 5094 through 5096.

Compliance required as indicated.

Recent calibration of several airplanes has revealed a difference in the airspeed and altimeter system static position error from the values presented in the AFM. These differences are in excess of tolerances which can be accepted as normal deviation from an Airplane Flight Manual calibration curve. To detect similar discrepancies, the following is required unless the system has previously been calibrated in accordance with the referenced manufacturer's instructions.

Within the next 100 hours' time in service after the effective date of this AD, calibrate the pitot static system in accordance with the instructions given in Lockheed-Georgia Service Bulletin 329-250, Section 2a through 2p, or later FAA approved revision; or in an equivalent manner approved by the Chief, Engineering and Manufacturing Branch, FAA Southern Region.

This amendment becomes effective April 19, 1968.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 2A15](https://openairdocs.org/tcds/2A15): Lockheed Martin Corporation; names 3 of 4 models: 1329-23D, 1329-23A, 1329-23E

## 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 (1 by airframe model, 0 by engine model)
- Makers: Lockheed 1

Models with the most aircraft:

- [Lockheed 1329-23E](https://openairdocs.org/model/lockheed-1329-23e): 1 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/68-08-07/models.md
Every aircraft: https://openairdocs.org/ad/68-08-07/aircraft.md

Its text cites no advisory circulars or STCs.

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