Airworthiness Directive · Amendment 39-17242 · Main landing gear strut/axle/truck
Aeronautical Accessories, Inc., High Landing Gear Forward Crosstube Assembly
This AD applies to high landing gear forward crosstube assembly (crosstube), part number (P/N) 212-321-103, installed on Agusta S.p.A. Model AB412 and AB412EP and Bell Helicopter Textron, Inc. Model 205A, 205A-1, 205B, 212, 412, 412CF, and 412EP helicopters, certificated in any category.
We are adopting a new airworthiness directive (AD) for Aeronautical Accessories, Inc. (AAI) high landing gear forward crosstube assemblies (crosstubes) installed on Agusta S.p.A. (Agusta) Model AB412 and AB412EP; and Bell Helicopter Textron, Inc. (Bell) Model 205A, 205A-1, 205B, 212, 412, 412CF, and 412EP helicopters during production or based on a supplemental type certificate (STC). This AD requires counting and recording the total number of landings for the crosstubes, and inspecting the crosstubes and replacing them if a crack or other damage exists. This AD was prompted by two reports from the field of failed crosstubes. The actions are intended to prevent failure of a crosstube, collapse of the landing gear, and subsequent loss of control of the helicopter.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(1) Within 50 hours time-in-service (TIS) after the effective date of this AD:
(i) Create a component history card or equivalent record for the crosstube by following the Accomplishment Instructions, Part A, paragraph 1., of AAI Alert Service Bulletin No. AA-08055, Revision B, dated August 12, 2009 (ASB).
(ii) Determine and record on the component history card or equivalent record the total number of landings for the crosstube. If the landing information is unavailable, estimate the number by multiplying the airframe hours TIS by 10. Continue to count and record the number of landings for the crosstube. For the purposes of this AD, a landing would be counted anytime the helicopter lifts off into the air and then lands again with any further reduction of the collective after the landing gear touches the ground.
(2) Within 50 hours TIS after the effective date of this AD or before reaching a total of 7,500 landings on any crosstube, whichever occurs later:
(i) Prepare the crosstube inspection areas as described in the Accomplishment Instructions, Part B, paragraphs 1. through 5. and Figure 1, of the ASB.
(ii) Using a 10X or higher power magnifying glass and a bright light, visually inspect the prepared areas of the crosstube for a crack. If there is a crack, before further flight, replace the crosstube with an airworthy crosstube.
(iii) If there is no crack, following the inspection, prime and paint the inspection areas by following the Accomplishment Instructions, Part B, paragraphs 7. and 8., of the ASB. If there is any corrosion or other damage, perform the replacement or repair required in paragraph (e)(5)(iv) of this AD before priming and painting the inspection areas.
(3) Thereafter, at intervals not to exceed 200 landings, clean the crosstube inspection areas by following the Accomplishment Instructions, Part C, paragraph 1., of the ASB. Using a 10X or higher power magnifying glass and a bright light, visually inspect the clear-coated areas of the crosstube for a crack. If there is a crack, before further flight, replace the crosstube with an airworthy crosstube.
(4) Within 30 days after the effective date of this AD or before reaching a total of 10,000 landings on any crosstube, whichever occurs later, and thereafter at intervals not to exceed 2,500 landings or 12 months, whichever occurs first, determine the horizontal deflection of the crosstube from the centerline of the helicopter (BL 0.0) to the outside of the skid tubes by following the Accomplishment Instructions, Part D, paragraphs 1. and 2., of the ASB. If the crosstube measures outside any of the limits depicted in Figure 2 of the ASB, before further flight, replace the crosstube with an airworthy crosstube.
(5) Within 3 months after the effective date of this AD or before reaching a total of 12,500 landings on any crosstube, whichever occurs later, and thereafter at intervals not to exceed 5,000 landings:
(i) Remove and disassemble the landing gear assembly and crosstube to prepare for a fluorescent penetrant inspection (FPI) by following the Accomplishment Instructions, Part E.1, paragraphs 1. through 6., of the ASB.
(ii) Clean and prepare the crosstube by removing the sealant and paint as described in the Accomplishment Instructions, Part E.2, paragraphs 1. through 3. and Figure 3, of the ASB.
(iii) Perform an FPI of the crosstube in the areas depicted in Figure 3 of the ASB for a crack, any corrosion, a nick, scratch, dent, or any other damage by following the Accomplishment Instructions, Part E.3, paragraph 1., of the ASB. If there is a crack, before further flight, replace the crosstube with an airworthy crosstube.
(iv) If there is any corrosion or a nick, scratch, dent, or any other damage, before further flight, repair the crosstube to an airworthy configuration if the damage is within the maximum repair damage limits or replace the crosstube with an airworthy crosstube. Chapter 3.5 Repair, Table 1. and Figure 3 of the AAI Instructions for Continued Airworthiness for Crosstubes, Report No. AA-01136, Revision K, dated February 15, 2012, contains the maximum repair damage limits and repair procedures.
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.
