(OVER)

SERVICE

BULLETIN

Date: June 12, 2015 (S)

NO. 1283

Subject: Cabin Altitude Encoder Installation

Modification

Models Affected: Serial Numbers Affected:

PA-46-350P Mirage/M350 4636460, 4636463 through 4636632, 

4636634 through 4636662

PA-46-500TP Meridian/M500 4697340, 4697399 through 4697591, 4697593 through 

4697595, 4697597, 4697598 

Compliance Time:

Part I: Modification is to be made prior to next flight. If necessary, operators are allowed 

up to 10 hours of operation in order to reach a maintenance facility capable of 

performing the modification mandated by Part I of this service bulletin, provided 

that instructions in the CAUTION statement below are followed prior to each flight.

CAUTION: as part of each preflight check, the owner/

operator shall grasp the knurled holddown nut

with a bare hand and verify that the nut is tight

and secure, Until the aircraft is in full compliance

with all instructions in Part I of this service

bulletin. Refer to Figures 1 and 2.

Part II: Compliance is to be accomplished on a recurring basis, at an interval not to 

exceed 50 hours time in service. 

Approval: The engineering aspects of this service document have been shown to comply 

with the applicable Federal Aviation Regulations and are FAA approved.

SAFETY INTENT: If not properly secured, the cabin altitude encoder may come free from its mounting 

bracket. If this should occur during flight, this cabin altitude encoder may interfere 

with full motion of the elevator flight control system, which could lead to loss of 

control of the aircraft.

CONFIGURATION 

DESCRIPTION: This service bulletin provides instructions for the modification of the cabin altitude 

encoder installation by adding cable ties, and applying thread-locking fluid to the 

knurled holddown nut, in order to provide an additional measure of component 

security.

PIPER CONSIDERS

COMPLIANCE MANDATORY

ATA: 2130

Piper Aircraft, Inc.

2926 Piper Drive

Vero Beach, FL, U.S.A. 32960
SERVICE BULLETIN NO. 1283 PAGE 2 of 5

Instructions:

Note: Some steps in these instructions are identified as “required for compliance” (RC). If this service bulletin 

is mandated by an airworthiness directive (AD), the steps identified as RC must be done to comply with 

the AD. Steps not identified as RC are recommended and may be deviated from, done as a part of other 

actions, or done with accepted methods different from those given in SB, if the RC steps can be done and 

the airplane can be put back in a serviceable condition.

NOTE: Temporary removal of the crew seats may be required to accomplish the modification described below.

NOTE: These instructions are intended as a temporary solution. This service publication will be revised at a later 

date to communicate the final, permanent solution for securing the cabin altitude encoder to the airframe.

CAUTION: as part of each preflight check, the owner/operator shall grasp

the knurled holddown nut with a bare hand and verify that the nut

is tight and secure, Until the aircraft is in full compliance with all 

instructions in Part I of this service bulletin. Refer to Figures 1 and 2.

Part I. Modification

1. RC – Locate the cabin altitude encoder (GAE 43, Garmin part number 013-00066-00; Sandia SAE 5-35), which 

provides cabin pressure data, installed forward of the instrument panel (see Figures 1 and 2).

2. RC – Secure the cabin altitude encoder to its mounting bracket with a minimum of two (2) cable ties, oriented 

as shown in Figure 3. Cable ties shall conform to military specification MS3367, and are available from several 

manufacturers, including Thomas & Betts, Avery Dennison, and Panduit. Trim the cable tie tails that extend 

beyond the cable tie head, to avoid interference with adjacent components. 

NOTE: Removal of the cabin altitude encoder from its mounting bracket is not required to accomplish the 

modification described in Part I, Step 2 of this service bulletin. 

RC – Cable ties should be snug, but not overly tightened, so as to avoid chafing against the sharp outside 

corners of the cabin altitude encoder housing. The proper tension can be achieved manually, without the use 

of a cable tie tool. 

RC – If cable ties are found already installed, check their condition and security; replace on condition.

3. RC – Remove the knurled holddown nut (see Figure 3). Apply Loctite Threadlocker Blue 242, or an equivalent 

thread-locking fluid conforming to MIL-S-46163A or ASTM D5363, onto the nut’s threaded post. Reinstall the 

knurled holddown nut and tighten by hand. 

RC – If the knurled holddown nut and/or any cable ties associated with the cabin altitude encoder are removed 

for any reason after compliance with Part I of this service bulletin, it is mandatory that the affected aircraft be 

in compliance with Part I of this service bulletin prior to next flight. 

4. Make a logbook entry documenting compliance with Part I of this service bulletin. 

Part II. Inspection

1. RC – Check the condition and security of the cable ties that were installed in Part I. Replace the cable ties 

on condition.

2. RC – Check the security of knurled holddown nut and, on condition, reapply thread-locking fluid identified 

in Part I.

3. Make a logbook entry documenting compliance with Part II of this service bulletin.

RC – 
SERVICE BULLETIN NO. 1283 PAGE 3 of 5

LOOKING UPWARD AND FORWARD FROM COPILOT SIDE

FORWARD OF THE INSTRUMENT PANEL 

KNURLED

HOLDDOWN NUT 

(AT THE BACK OF 

THE UNIT, FORWARD 

POSITION IN 

THE AIRCRAFT)

FWD

Figure 1

Recommended Position to Check Security of Knurled Holddown Nut

OUTBD

UP

INSTRUMENT PANEL

LOOKING AFT

CABIN ALTITUDE ENCODER SEE DETAIL A

FIGURE 2

NOTE: The exact location of the encoder may vary from what is shown.

Figure 2

Instrument Panel - Typical
SERVICE BULLETIN NO. 1283 PAGE 4 of 5

Figure 3

Cabin Altitude Encoder Installation – Three View

CABIN ALTITUDE ENCODER

KNURLED HOLDDOWN NUT

DETAIL A

LOOKING AFT

ADJACENT COMPONENTS OMITTED FOR CLARITY

FWD

MS3367

CABLE TIE

MIN. 2 REQ’D

TOP VIEW

BOTTOM VIEW

MOUNTING

BRACKET

UP

FWD

KNURLED HOLDDOWN NUT
SERVICE BULLETIN NO. 1283 PAGE 5 of 5

MATERIAL REQUIRED: RC – Part I only: A minimum quantity of two (2) cable ties, MS3367 series, 

per aircraft; Loctite Threadlocker Blue 242, or an equivalent thread-locking fluid 

(meeting MIL-S-46163A or ASTM D5363), quantity as required

AVAILABILITY OF PARTS: Procure locally

Effectivity date: This service bulletin is effective upon receipt.

Summary: Applicable factory participation is limited to new aircraft in warranty at the time of 

compliance. 

Please contact your Factory Authorized Piper Service Facility to make 

arrangements for compliance with this service bulletin in accordance with the 

compliance time indicated.

Note: Please notify the factory of any address/ownership corrections. Changes should include aircraft model, 

serial number, and current owner’s name and address.

Corrections and/or changes should be directed to:

PIPER AIRCRAFT, INC.

Attn: Customer Service

2926 Piper Drive

Vero Beach, FL 32960