Airworthiness Directive · Amendment 39-11499 · Raytheon Model BAe.125 Series 1000A and 1000B Airplanes and Model Hawker 1000 Series Airplanes
Raytheon Model BAe.125 Series 1000A and 1000B Airplanes and Model Hawker 1000 Series Airplanes
All Model BAe.125 series 1000A and 1000B airplanes and Model Hawker 1000 series airplanes, certificated in any category.
This amendment adopts a new airworthiness directive (AD), applicable to all Raytheon Model BAe.125 series 1000A and 1000B airplanes and Model Hawker 1000 series airplanes, that requires an inspection to determine the integrity of the duct connection on both ends of the turbine air discharge duct in the air conditioning system; an inspection to measure the bead height on the ends of the turbine air discharge duct; and corrective actions, if necessary. This amendment is prompted by reports indicating that the turbine air discharge duct disconnected from the cold air unit (CAU) or water separator due to insufficient bead height on the ends of the turbine air discharge duct. The actions specified by this AD are intended to prevent such disconnection from the CAU or water separator, which could result in cabin depressurization.
Required as indicated, unless accomplished previously.
To prevent the turbine air discharge duct in the air conditioning system from disconnecting from the CAU or water separator in flight, which could result in cabin depressurization, accomplish the following:
Inspections
(a) Within 25 flight hours after the effective date of this AD, perform a general visual inspection to determine the integrity of the duct connections (i.e., ensure that the duct and securing clamps are in place, the sleeve is central to the joint gap, and the clamps are clear of the duct bead) on both ends of the turbine air discharge duct in accordance with Raytheon Service Bulletin SB 21-3108, dated November 1998. If any discrepancy is detected, prior to further flight, adjust the clamps in accordance with the service bulletin.
Note 2: For the purposes of this AD, a general visual inspection is defined as: ``A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or drop-light, and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.''
(b) Within 300 flight hours or 6 months after the effective date of this AD, whichever occurs first, perform a one-time detailed inspection to measure the bead height on the ends of the turbine air discharge duct in accordance with Raytheon Service Bulletin SB 21-3108, dated November 1998. If the bead height does not conform to the dimension shown in the service bulletin, prior to further flight, either rework the duct or replace the duct with a new duct, in accordance with the service bulletin.
Note 3: For the purposes of this AD, a detailed inspection is defined as: ``An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.''
Spares
(c) As of the effective date of this AD, no person shall install a turbine air discharge duct, part number 25-9VF425-1A, on any airplane, unless that duct has been inspected in accordance with Part II of Raytheon Service Bulletin SB 21-3108, dated November 1998.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
