AD 76-11-07

Airworthiness directive · Magnetic Compass Deviations · Piper PA-23-250 and PA-23-250 (Navy UO-1)

Effective
June 4, 1976
Published
June 1, 1976
Issued
May 21, 1976
Models
PA-23-250, PA-23-250 (Navy UO-1)
Data sheet
TCDS1A10
Registered aircraft
899 matched by model
Product
Aircraft · Small airplane
Amendment
39-2628

Unofficial copy of the text in the FAA’s Dynamic Regulatory System. The FAA’s own copy is the authoritative one. DRS record last changed November 21, 2025.

On this page

The airworthiness directive

76-11-07 PIPER: Amendment 39-2628. Applies to Model PA-23-250 (6 place) S/Ns 27-3837, 27-3944 to 27-7554092 inclusive; 27-7554094 to 27-7554159 inclusive; 27-7554161 to 27-7654018 inclusive; 27-7654020 to 27-7654024 inclusive; 27-7654026 to 27-7654036 inclusive.

Compliance required within the next 100 hours' time in service after the effective date of this AD unless already accomplished.

To prevent the hazards associated with the excess magnetic compass deviations when the landing/taxi lights and/or heater are turned on, accomplish the following:

(a) Check the magnetic compass function to ascertain operation of the magnetic compass within acceptable limits in accordance with the instructions given in Service Bulletin No. 493, dated March 25, 1976, or with an approved alternate method.

(b) If compass deviation exceeds 10 degrees, a wiring modification is required in accordance with the referenced service bulletin or an approved alternate method.

(c) Upon request with substantiating data submitted through an FAA Maintenance Inspector, the compliance time specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region who must also approve alternate methods of compliance. (Piper Service Bulletin No. 493, dated March 25, 1976, covers this subject).

This amendment is effective June 4, 1976.

Affected TCDS · 1

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 899

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

By aircraft maker
  • Piper899 aircraft
By year built
19531995
Registered aircraft by year built: 724 aircraft
19531
196033
196113
196221
196319
196425
196544
196659
196731
196839
196949
197019
197124
197227
197344
197449
197536
197652
197735
197836
197946
198011
198110
19951

175 with no year recorded

By model

Aircraft

See all 899 aircraft