Airworthiness Directive · Amendment 39-11553 · Raytheon Model Hawker 800 and 1000 Airplanes and Model DH.125, HS.125, BH.125, and BAe.125 Series Airplanes
Raytheon Model Hawker 800 and 1000 Airplanes and Model DH.125, HS.125, BH.125, and BAe.125 Series Airplanes
Models and series of airplanes as listed in the applicable service bulletin(s) specified in Table 1 of this AD, certificated in any category.
| Model of Airplane | Raytheon Service Bulletin | Date of Service Bulletin |
|---|---|---|
| DH.125, HS.125, BH.125 series 1A, 1B, 3A, 3B, 400A, 400B, 401B, 403A, 403B, 600A, 600B, 700A, and 700B airplanes | SB 35-3169 | September 1998. |
| BAe.125 series 800A (C-29A) airplanes | SB 35-3171 | September 1998. |
| BAe.125 series 800A and 800B airplanes, and Hawker 800 airplanes | SB 35-3034 and SB 35-3170 | September 1998. |
| BAe.125 series 1000A and 1000B airplanes, and Hawker 1000 airplanes | SB 35-3167 and SB 35-3168 | September 1998. |
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been 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 Hawker 800 and 1000 airplanes and Model DH.125, HS.125, BH.125, and BAe.125 series airplanes, that requires replacement of cadmium plated fittings and cone caps in the oxygen system plumbing with improved fittings and cone caps, a detailed visual inspection of the oxygen system plumbing in the area of the replaced parts, and corrective actions, if necessary. This amendment is prompted by reports indicating that a field survey of the affected parts revealed that a reaction process was occurring, which resulted in cadmium flaking. The actions specified by this AD are intended to prevent flaking of cadmium from certain oxygen system plumbing fittings and cone caps from blocking the valves and impairing the function of the oxygen system, which could deprive the crew and passengers of necessary oxygen during an emergency that requires oxygen.
To prevent flaking of cadmium from certain oxygen system plumbing fittings and cone caps from blocking the valves and impairing the function of the oxygen system, which could deprive the crew and passengers of necessary oxygen during an emergency that requires oxygen, accomplish the following:
(a) For Model DH.125, HS.125, BH.125 series 1A, 1B, 3A, 3B, 400A, 400B, 401B, 403A, 403B, 600A, 600B, 700A and 700B airplanes: Within 6 months after the effective date of this AD, replace the cadmium plated cone caps in the oxygen system plumbing with improved cone caps, and perform a detailed visual inspection of the removed cone caps, tee-piece and sleeve for evidence of flaking or corrosion; in accordance with Raytheon Service Bulletin SB 35-3169, dated September 1998. If any flaking or corrosion is detected, prior to further flight, clean the tee-piece and sleeve, and perform an oxygen system flow check in accordance with the service bulletin. If any discrepancy is found during the flow check, prior to further flight, repair the oxygen system in accordance with the service bulletin, except as required by paragraph (e) of this AD.
Note 2: For the purposes of this AD, a detailed visual 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.”
(b) For Model BAe.125 series 800A (C-29A) airplanes: Within 6 months after the effective date of this AD, replace the cadmium plated cone caps in the oxygen system plumbing with improved cone caps, and perform a detailed visual inspection of the removed cone caps, tee-piece and sleeve for evidence of flaking or corrosion; in accordance with Raytheon Service Bulletin SB 35-3171, dated September 1998. If any flaking or corrosion is detected, prior to further flight, clean the tee-piece and sleeve, and perform an oxygen system flow check in accordance with the service bulletin. If any discrepancy is found during the flow check, prior to further flight, repair the oxygen system in accordance with the service bulletin, except as required by paragraph (e) of this AD.
(c) For Model BAe.125 series 800A and 800B airplanes and Model Hawker 800 airplanes: Within 6 months after the effective date of this AD, replace the cadmium plated cone caps in the oxygen system plumbing with improved cone caps, and perform a detailed visual inspection of the removed cone caps, tee-piece and sleeve for evidence of flaking or corrosion; in accordance with Raytheon Service Bulletins SB 35-3034 or SB 35-3170, both dated September 1998, as applicable. If any flaking or corrosion is detected, prior to further flight, clean the tee-piece and sleeve, and perform an oxygen system flow check in accordance with the service bulletin. If any discrepancy is found during the flow check, prior to further flight, repair the oxygen system in accordance with the service bulletin, except as required by paragraph (e) of this AD.
(d) For Model BAe.125 series 1000A and 1000B airplanes and Model Hawker 1000 series airplanes: Within 6 months after the effective date of this AD, replace the cadmium plated fittings in the oxygen system plumbing with improved fittings, and perform a detailed visual inspection of the removed fittings and the pipe connections for evidence of flaking or corrosion; in accordance with Raytheon Service Bulletin SB 35-3167 or SB 35-3168, both dated September 1998, as applicable. If any flaking or corrosion is detected, prior to further flight, clean the pipe connections, and perform an oxygen system flow check in accordance with the service bulletin. If any discrepancy is found during the flow check, prior to further flight, repair the oxygen system in accordance with the service bulletin, except as required by paragraph (e) of this AD.
(e) If any discrepancy is found during a flow check required by paragraph (a), (b), (c), or (d) of this AD and the applicable service bulletin specifies to contact the manufacturer for a repair disposition, prior to further flight, repair the oxygen system in accordance with a method approved by the Manager, Wichita Aircraft Certification Office (ACO), FAA, Small Airplane Directorate.
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.
