Commonwealth legislation

AD/BEECH 90/91 - Pressurisation Control System Pneumatic Tubing Inspection

In ForceCTH

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

3/10 complexity

What this does: Owners/operators of the listed Beechcraft 90/65‑90 series aeroplanes must inspect and re‑route the environmental air‑conditioning and pressurisation pneumatic tubing in accordance with Raytheon Mandatory Service Bulletin 2676. Compliance is required at the next scheduled inspection or within 200 flight hours.

Why it matters: The measure responds to manufacturer findings that heat from the co‑pilot’s foot warmer can soften or rupture plastic tubing, risking loss of vacuum to outflow/safety valves (preventing depressurisation) or loss of the de‑icing indicator. Operators pay for and schedule the maintenance action.

JSON API

Deep dive

Want the full deep dive?

Zoe can write the in-depth analysis on top of the summary above: how it works, who it affects and what each part actually does.

Current sections

Direct links to the current provisions in AD/BEECH 90/91 - Pressurisation Control System Pneumatic Tubing Inspection.

AD/BEECH 90/91 - Pressurisation Control System Pneumatic Tubing Inspection

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

View image in the official source
Beechcraft 90 and 65-90 (King Air) Series Aeroplanes

AD/BEECH 90/91 Pressurisation Control System

Pneumatic Tubing Inspection

2/98

Applicability: All Beech 90 series aircraft with serial numbers LJ-683 through LJ-1463, LW-177 through LW-347, LA-1 through LA-236 and LL-1 through LL-61.

Requirement: Inspect and re-route the environmental air conditioning and pressurisation control system pneumatic tubing in accordance with Raytheon Aircraft Mandatory SB 2676 dated January, 1997.

Note: FAA AD 97-23-17 Amdt 39-10207 and DGAC AD 97-353-(AB) refers.

Compliance: Unless previously carried out at the next schedule inspection but no later than the next 200 hours’ time in service from the effective date of this Directive.

This airworthiness directive becomes effective on 29 January 1998.

Background: This directive being raised on receipt of FAA AD and advice that when a pilot requested a passenger to open the cabin door a passenger was injured when ejected from the aircraft onto the tarmac.

Subsequent investigation by the manufacturer confirmed that heat from the co pilot’s foot warmer outlet and associated plumbing can soften the plastic pressurisation control system pneumatic tubing sufficiently to cause permanent collapse when the line is subject to vacuum. This will result in loss of vacuum to the outflow/safety valves and this could prevent depressurisation of the aircraft. If the cabin door is operated with the aircraft partially pressurised injury to passengers and/or ground personnel may occur.

The de-icing indicator pneumatic tubing also has the potential for heat damage from the co-pilot’s foot warmer. This tubing could rupture rendering the de-icing indicator inoperative.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/BEECH 90/91 - Pressurisation Control System Pneumatic Tubing Inspection