Airworthiness Directive · Amendment 39-15916 · M7 Aerospace LP Models SA226-AT, SA226-T, SA226-TC, SA227-AC (C-26A), SA227-AT, SA227-BC (C-26A), SA227-CC, and SA227-DC (C-26B) Airplanes
M7 Aerospace LP Models SA226-AT, SA226-T, SA226-TC, SA227-AC (C-26A), SA227-AT, SA227-BC (C-26A), SA227-CC, and SA227-DC (C-26B) Airplanes
This AD applies to Models SA226-AT, SA226-T, SA226-TC, SA227-AC (C-26A), SA227-AT, SA227-BC (C-26A), SA227-CC, and SA227-DC (C-26B) airplanes, all serial numbers, that are certificated in any category.
We are adopting a new airworthiness directive (AD) to supersede AD 2008-12-16, which applies to certain M7 Aerospace LP SA226 and SA227 series airplanes. AD 2008-12-16 currently requires you to inspect wires and tube assemblies for chafing, arcing, or insufficient clearance between components. If chafing, arcing, or insufficient clearance between components is found, AD 2008-12-16 requires you to clear, repair, and/or replace all chafed wires, components, and tube assemblies. AD 2008-12-16 also requires you to cover the four-gauge wires leaving the battery box with firesleeving and secure them with a clamp. Since we issued AD 2008-12-16, M7 Aerospace LP has notified us that Model SA227-BC (C-26A) was inadvertently left out of the Applicability section of the AD, and they updated some of the service information due to parts availability. Operators have also identified issues with model applicability that needed clarification. Consequently, this AD retains the actions of AD 2008-12-16, adds Model SA227-BC (C-26A) to the Applicability section, and regroups the models for clarification. We are issuing this AD to detect and correct chafing of electrical wires, components, and tube assemblies. This condition could result in arcing of exposed wires with consequent burning of a hole in a hydraulic line or the bleed air line. This failure could lead to a hydraulic fluid leak and a possible fire in the engine nacelle compartment.
To address this problem, you must do the following, unless already done:
| Actions | Compliance | Procedures |
|---|---|---|
| (1) For the following model and serial number (S/N) airplanes, inspect the main battery leads running forward from the battery compartment for deterioration, cover the four-gauge wires leaving the battery box with firesleeving, and secure them with a clamp: (i) SA226-AT, S/N AT-001 through AT-419; (ii) SA226-T, S/N T-201 through T-248; (iii) SA226-TC, S/N TC-201 through TC-419; (iv) SA227-AC (C-26A), S/N AC-420 through AC-539, AC-541, AC-543, AC-544, AC-547 through AC-551; and (v) SA227-AT, S/N AT-423 through AT-551. | Within 250 hours time-in-service (TIS) after July 23, 2008 (the effective date of AD 2008-12-16). | Use the following service information as applicable: (A) For Models SA226-AT, SA226-T, and SA226-TC airplanes: Follow M7 Aerospace SA226 Series Service Bulletin No. 226-24-019, revised: November 21, 2008; or Fairchild Aircraft Corporation SA226 Series Service Bulletin No. SB 24-019, revised: May 17, 1983; or (B) For Models SA227-AC (C-26A) and SA227-AT airplanes: Follow M7 Aerospace SA227 Series Service Bulletin No. 227-24-001, revised: November 21, 2008; or Fairchild Aircraft Corporation SA227 Series Service Bulletin No. SB24-001, revised: May 17, 1983. |
| (2) For the following model and S/N airplanes, reroute the hydraulic tube assemblies in the right wing leading edge, reroute the battery cables and 22-gauge wire bundle, and install a new access panel forward of the battery box: (i) SA226-AT, S/N AT-001 through AT-074; (ii) SA226-TC, S/N TC-201 through TC-419; (iii) SA227-AC (C-26A), S/N AC-420 through AC-539, AC-541, AC-543, AC-544, AC-547 through AC-550; and (iv) SA227-AT, S/N AT-423 through AT-551. | Before further flight after the modification required in paragraph (e)(1) of this AD and you were not able to obtain a minimum 0.50-inch clearance between the bleed air line and the tubing on the battery cables. | Use the following service information as applicable: (A) For Models SA226-AT, and SA226-TC airplanes: Follow M7 Aerospace SA226 Series Service Bulletin No. 226-24-020, revised: August 4, 2008; or Fairchild Aircraft Corporation SA226 Series Service Bulletin No. SB 24-020, revised: February 15, 1984; or (B) For Models SA227-AC (C-26A) and SA227-AT, airplanes: Follow M7 Aerospace SA227 Series Service Bulletin No. 227-24-002, revised: November 21, 2008; or Fairchild Aircraft Corporation SA227 Series Service Bulletin No. SB24-002, revised: February 15, 1984. |
| (3) For model SA226-AT, SA226-T, SA226-TC, SA227-AC (C-26A), SA227-AT, SA227-CC, and SA227-DC (C-26B) airplanes, all S/N: Inspect electrical wires and components, hydraulic tube assemblies, and bleed air tube assemblies at the left hand and right hand (LH/RH) inboard wing leading edge/battery box areas, LH/RH wing stations 51.167 to 81.174, and at all feed-through locations into the LH/RH inboard keelson for any evidence of chafing or arcing. | Within 250 hours TIS after July 23, 2008 (the effective date of AD 2008-12-16). Repetitively thereafter inspect at intervals not to exceed 12 months. | Use the following service information as applicable: (i) For Models SA226-AT, SA226-T, and SA226-TC airplanes: Follow M7 Aerospace SA226 Series Service Bulletin No. 226-24-036, revised November 21, 2008; or M7 Aerospace SA226 Series Service Bulletin No. 226-24-036, issued: September 19, 2007; (ii) For Models SA227-AC (C-26A) and SA227-AT, airplanes: Follow M7 Aerospace SA227 Series Service Bulletin No. 227-24-019, revised: November 21, 2008; or M7 Aerospace SA227 Series Service Bulletin No. 227-24-019, issued: September 19, 2007; or (iii) For Models SA227-CC and SA227-DC (C-26B) airplanes: Follow SA227 Series Commuter Category Service Bulletin No. CC7-24-010, revised November 21, 2008; or SA227 Series Commuter Category Service Bulletin No. CC7-24-010, issued September 19, 2007. |
| (4) For model SA227-BC (C-26A) airplanes, all S/N: Inspect the main battery leads running forward from the battery compartment for any evidence of insulation deterioration. | Within 250 hours TIS after July 2, 2009 (the effective date of this AD). | Follow M7 Aerospace SA227 Series Service Bulletin No. 227-24-001, revised: November 21, 2008. |
| (5) For model SA227-BC (C-26A) airplanes, all S/N: Inspect electrical wires and components, hydraulic tube assemblies, and bleed air tube assemblies at LH/RH inboard wing leading edge/battery box areas, LH/RH wing stations 51.167 to 81.174, and at all feed-through locations into the LH/RH inboard keelson for any evidence of insulation deterioration, chafing, or arcing. | Within 250 hours TIS after July 2, 2009 (the effective date of this AD). Repetitively thereafter inspect at intervals not to exceed 12 months. | Follow M7 Aerospace SA227 Series Service Bulletin No. 227-24-019, revised: November 21, 2008. |
| (6) For all model and S/N airplanes: Clear, repair, and/or replace all electrical wires and components, hydraulic tube assemblies, and bleed air tube assemblies, in the inspection area and feed-through locations that show any sign of insulation deterioration, chafing, or arcing, as required. | Before further flight after any inspection required in paragraphs (e)(1), (e)(3), (e)(4), and (e)(5) of this AD where any evidence of insulation deterioration, chafing, or arcing was found. | Use the service information from paragraphs (e)(1), (e)(3), (e)(4), and (e)(5) of this AD, as applicable. |
Note: Although not a requirement of this AD, you may incorporate Swearingen Aviation Corporation SA226 Series Service Bulletin No. 57-010, revised: December 5, 1975, on those airplanes that have not installed the access panel. Installation of the access panel will simplify the incorporation of the service bulletins referenced in this AD and future inspections of the areas of concern.
