Airworthiness Directive · Amendment 39-16289 · Electric power
Hawker Beechcraft Corporation (Type Certificate No. A00010WI Previously Held by Raytheon Aircraft Company) Model 390 Airplanes
This AD applies to Model 390 airplanes, serial numbers RB-4 through RB-248, that are certificated in any category.
We are adopting a new airworthiness directive (AD) for certain Hawker Beechcraft Corporation Model 390 airplanes. This AD requires you to inspect the essential bus lightning strike protection for proper installation of metal oxide varistor (MOV) and spark gap wiring. This AD also requires you to rework the wiring as necessary to achieve the required lightning strike/surge protection. This AD results from a report that the wires to the MOV and spark gap were swapped. We are issuing this AD to detect and correct improper installation of the MOV and spark gap wiring, which could result in overload of the MOV in a lightning strike and allow electrical energy to continue to the essential bus and disable equipment that receives power from the essential bus. The disabled equipment could include the autopilot, anti-skid system, hydraulic indicator, spoiler system, pilot primary flight display, audio panel, or the <greek-i>1 air data computer. This failure could lead to a significant increase in pilot workload during adverse operating conditions.
To address this problem, you must do the following, unless already done:
| Actions | Compliance | Procedures |
|---|---|---|
| (1) Inspect the essential bus lightning strike protection for proper installation of MOV and spark gap wiring. | Within the next 200 hours time-in-service after June 21, 2010 (the effective date of this AD) or within the next 12 months after June 21, 2010 (the effective date of this AD), whichever occurs first. | Follow Hawker Mandatory Service Bulletin SB 24-3995, issued September 2009. |
| (2) Where improper wiring installation is found, rework the essential bus lightning strike wiring installation for the MOV and spark gap. | Before further flight after the inspection in paragraph (f)(1) of this AD. | Follow Hawker Mandatory Service Bulletin SB 24-3995, issued September 2009. |
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
