Airworthiness Directive · Amendment 39-11949 · Raytheon Model DH.125, Model HS.125, Model BH.125, Model BAe.125 Series 800A (Including Major Variants C-29A and U1-25), Model Hawker 800, Model Hawker 800XP, and Model Hawker 1000 Series Airplanes
Raytheon Model DH.125, Model HS.125, Model BH.125, Model BAe.125 Series 800A (Including Major Variants C-29A and U1-25), Model Hawker 800, Model Hawker 800XP, and Model Hawker 1000 Series Airplanes
Model DH.125, Model HS.125, Model BH.125, Model BAe.125, Model Hawker 800, Model Hawker 800XP, and Model Hawker 1000 series airplanes; as listed in Raytheon Aircraft Service Bulletin SB 34-3207, dated August 1999; excluding those airplanes on which all pitot/static drain vent valves have been modified with an insert in accordance with Raytheon Aircraft Repair Design Office instructions; certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (f) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD), applicable to certain Raytheon Model DH.125, Model HS.125, Model BH.125, Model BAe.125 Series 800A, Model Hawker 800, Model Hawker 800XP, and Model Hawker 1000 series airplanes, that requires leak checks and inspections for corrosion of the pitot/static and stall vent drain valves, and replacement of certain components, if necessary. This amendment is prompted by reports of plugged or taped drain valves as well as consequent corrosion of certain drain valves. The actions specified by this AD are intended to prevent erroneous altimeter and airspeed indications due to plugged or taped pitot/static and stall vent drain valves.
To prevent erroneous altimeter and airspeed indications due to plugged or taped pitot/static and stall vent drain valves, accomplish the following:
(a) Within 300 hours time-in-service after the effective date of this AD: Drain the pitot/static and stall vent drain valves, and perform a leak test of the systems, in accordance with Raytheon Aircraft Service Bulletin SB 34-3207, dated August 1999. If all drain valves are operating correctly and the leak test is passed successfully, thereafter, repeat the leak test at intervals not to exceed 300 hours time-in-service.
(b) If all drain valves are operative, but any valve does not pass the leak test required by paragraph (a) of this AD: Prior to further flight, accomplish the actions specified in paragraph (b)(1), (b)(2), or (b)(3) of this AD.
(1) Apply a temporary seal of the drain valve(s) in accordance with Raytheon Aircraft Service Bulletin SB 34-3223, dated August 1999. Within 300 hours time-in-service after the accomplishment of the temporary seal, accomplish the requirements of paragraph (b)(2) or (b)(3) of this AD.
(2) Replace the drain valve components with new or serviceable drain valve components in accordance with Raytheon Aircraft Service Bulletin SB 34-3207, dated August 1999, and perform the leak test specified in paragraph (a) of this AD. Thereafter, repeat the requirements of paragraph (a) of this AD at intervals not to exceed 300 hours time-in-service.
(3) Modify the drain valves in accordance with Raytheon Aircraft Service Bulletin SB 34-3282, dated August 1999. Thereafter, repeat the requirements of paragraph (a) of this AD at intervals not to exceed 300 hours time-in-service unless all the drain valves have been modified. Accomplishment of this modification on ALL drain valves constitutes terminating action for the requirement to perform repetitive leak tests.
(c) If any drain valve is inoperative (e.g., plugged or taped), whether or not any leaking is detected: Prior to further flight, disassemble the valve and clean all obstructions in accordance with Raytheon Aircraft Service Bulletin SB 34-3207, dated August 1999, and perform a general visual inspection for corrosion of the drain valve.
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 droplight, 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.”
(d) If no corrosion of the drain valves is detected, prior to further flight, perform the actions specified in either paragraph (d)(1) or (d)(2) of this AD at the time specified.
(1) Perform the leak test specified in paragraph (a) of this AD, and thereafter, repeat the leak test requirements at intervals not to exceed 300 hours time-in-service.
(2) Prior to further flight, modify any inoperative valve in accordance with Raytheon Aircraft Service Bulletin SB 34-3282, dated August 1999. Thereafter, repeat the leak test requirements of paragraph (a) of this AD at intervals not to exceed 300 hours time-in-service. Modification of ALL the drain valves constitutes terminating action for the requirement to perform repetitive leak tests.
(e) If any drain valve is corroded, prior to further flight: Inspect the connecting tubing for corrosion and replace any corroded valve or tubing with a new or serviceable valve or tubing in accordance with Raytheon Aircraft Service Bulletin SB 34-3207, dated August 1999. Accomplish the actions of paragraph (e)(1) or (e)(2) of the AD at the time specified.
(1) Prior to further flight, perform the leak test specified in paragraph (a) of this AD, and thereafter, repeat the leak test requirements of paragraph (a) of this AD at intervals not to exceed 300 hours time-in-service.
(2) Prior to further flight, modify any replaced drain valve in accordance with Raytheon Aircraft Service Bulletin SB 34-3282, dated August 1999. Thereafter, repeat the leak test requirements of paragraph (a) of this AD at intervals not to exceed 300 hours time-in-service. Modification of ALL the drain valves constitutes terminating action for the requirement to perform repetitive leak tests.
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.
