Because Owning And Flying Your Beechcraft Can Be Done Safely AND For Less Money!
  FAA AD 2008-13-17 on Beech Toggle Circuit Breaker Switches

FAA AD 2008-13-17




W31 Toggle Circuit Breaker (TCB) Switch

The un-insulated braided wire is the mode of failure.


On July 2nd, 2008 the FAA published AD 2008-13-17 against many of the Toggle Circuit Breaker Switches that are found in Beech Aircraft.


This AD requires that certain Beechcraft Part Number circuit breaker-type switches be replaced in F33, F33A, G33, V35B, A36, A36TC, B36TC, B55, D55, E55, A56TC, 58, 58P, 58TC, G58 and model 77 Skippers.


It becomes effective August 6th, 2008 and must be complied with within 12 months following the effective date.



11 June 2009 NEWS FLASH: ABS has secured an extension* for compliance with this AD. See more info HERE. Way to go ABS!


*FAA strings attached



20 November 2009 NEWS FLASH: GOOD NEWS, Williams Air Parts has received a PMA approval for an alternate circuit breaker to comply with this AD. The BAD NEWS (reported on 11/4/2009) is that it's MORE EXPENSIVE than the Tyco/Beechcraft breaker that is being provided to comply with the AD . On 11/24/2009 their site reported their PMA'd breaker at $140 each. See the Williams offering below and read more about the Williams Air offering HERE







The affected models and SNs extracted from the AD are below:


This AD applies to the following airplane models and serial numbers that have a part number (P/N) 35-380132-1 through 35-380132-53 circuit breaker toggle switch installed and are certificated in any category:


  Beech Model                                                        Serial Numbers

(1) F33 and G33                                           CD-1235 through CD-1304

(2) F33A                                                         CE-290 through CE-1791

(3) F33C                                                         CJ-26 through CJ-179

(4) V35B                                                         D-9069 through D-10403

(5) A36                                                            E-185 through E-3629 and E-3631 through E-3635

(6) A36TC and B36TC                                EA-1 through EA-695

(7) 95-B55                                                      TC-1913, TC-1936 through TC-2456

(8) D55                                                            TE-452 through TE-767

(9) E55                                                            TE-768 through TE-1201

(10) A56TC                                                    TG-84 through TG-94

(11) 58                                                            TH-1 through TH-2124

(12) 58P                                                         TJ-3 through TJ-497

(13) 58TC                                                      TK-1 through TK-151

(14) G58                                  TH-2126, TH-2127, TH-2131 through TH-2134, TH-2136, TH-2137,

                                                  TH-2139 through TH-2141 and TH-2143 through TH-2150

(15) 77 Skipper                                              WA-1 through WA-312


Some aircraft could have as many as 15 of these TCB switches in the airplane. Fortunately, my B55 is not affected by Serial Number.



Allied Electronics also carries the W31 TCB Switch


Read the ABS Article HERE


Read the latest 8/21/2008 ABS Update HERE highlighting the "fix" that Tyco has put into the replacement switch.


Read the 1/26/2009 ABS Update on FAA Refusal to Re-Review the AD HERE


Read the AD HERE


Read the W31 PDF Spec Sheet HERE


Read the FAA Narrative HERE


Read Beech Lister Jim B.'s Breaker Cross Reference List HERE*





Other Sources for the W31 TCB: Newark @ $21.53 and Mouser @ $26.27



EDITORIAL COMMENT FOLLOWS: You know, I really don't understand why it is that only Beechcraft circuits and airframes are the only places where these circuit breakers "let the smoke out" and in no other airframes where this breaker design must have found itself during all these years in the aviation industry. Things that make you go HMMMMMMM!



Here are the actual Tyco manufacturer comments regarding these switch designs that were provided to Beech Lister Ron G. and subsequently reported to me:


1. The old Beech TCB is provided by Tyco to Beech and isn't available directly from Tyco distributors. Tyco does not consider it to be obsolete, at least not yet. That old Beech TCB is Tyco part number W31-X1005-xx. (The last two digits "xx" represent the Amp rating.)


2. The new Beech part is provided by Tyco to Beech and isn't available directly from Tyco distributors. The Tyco part number is W31-X1017-xx. It includes the additional internal insulation that is described in the FAA AD.


3. The Tyco part number W31-X2M1G-xx, which is available from several distributors including Allied Electronics for less than $25, Newark Electronics, Mouser, and Spruce, does include the additional internal insulation as does the W31-X1017-xx part. However, the toggle handle shape and color is different from the Beech W31-X1017-xx part. Both the W31-X1017-xx part from Beech and the Tyco W31-X2M1G-xx have the amp rating stamped into the end of the toggle.



Joe F., a PE and A36 owner in New York, has provided a picture of the TYCO W31 switch in his panel alongside the Beech OE switches. Joe affectionately dubs the TYCO switch  "The LLC" switch for "Looks Like Crap" <vbg>! It's the one in the Beacon position....LOL



Nothing but full disclosure here at CSOBeech, so you and your mechanic decide what works for you. Thanks for the contribution Joe.



Here's a CB install  pirep from Leldon L.


I had told my 78 year old IA I would do the grunt work under the panel on his 1980 A36... and then we would do mine.


We started this morning on his first... got out all the tools, lights, fans ( only 100 today in Texas..but about 85 in his A/C hangar, pads, etc,etc).


The first one was definitely the "learning" one. It took me right at 4 hours total time from start to finish on his seven breakers. (he needed the ALT CB that I didn't)


With all the tools out and ready... and the experience of his.... I did my '76 A36's six CB's in ONE hour flat. Three important points I learned on our airplanes that may not to applicable to all... may not work on the 84 and newer panels, and maybe the P barons..... don't know enough about the 55/58 barons to say...


1. I learned that if I disconnected the load side of the CB's it was possible to remove all six CB's on the buss bar as a whole set... that really really saved a bunch of time. Installed the new CB's on the buss bar loosely on the workbench.....then reinstall the whole set at one time.


2. Beg, borrow, or steal a set of screw starters.... I used about a 8 inch one and it worked slicker than xxxxx. No dropped screws on reinstalling the wire terminals.


3. IF you plan on paying somebody else by the hour to do yours... I'd use a shop that has done a few... as previously noted... the second went a MUCH faster.


Of course, disconnect the battery... put down something on the floor to catch what you drop... you WILL drop something into the bilges if you don't!


Kind of a pisser... to summarize this whole questionable AD... twelve of the 13 breakers I did today were "Woods"... not supposed to have the failure mechanism of the AD... the last CB was one I bought 3 years ago from RAPID..


A source for Screw Starters is HERE and HERE



Thanks Leldon!



Here is an install pirep from Dr. Dave Rogers on his experience with his shop's breaker switch install:


At 9AM Monday the A-36 went in for the circuit breaker AD. There were seven breakers to replace. I handed the shop (SafeFlight at Bay Bridge W29) the breakers in their original Rapid bags with the appropriate function for each breaker marked on the bag. I also handed them all the original paperwork from Rapid. I included a copy of the breaker replacement tables from the AD with the appropriate entries marked and labeled with the appropriate function. Finally, I handed them a copy of Leldon's Pirep (above) and explained how I thought this should go and left to do some odds & ends on the E33A.


This was their first AD job. I wandered back a little over an hour later. The electrical sub-bus was out of the aircraft on the bench and the new breakers almost all installed in the sub-bus. I then wandered to my next meeting. Around noon I got a call that the job was finished, an ops check performed, the paperwork done and the aircraft would be back in the hangar shortly. I was pleased.


So, it looks like we have at least one shop in the Mid-Atlantic region that can do the job in a reasonable amount of time. Let's keep a list of maintenance shops that have done the AD in a reasonable amount of time.


Dave's Shop:


Safe Flight at W29

Phone: 410-643-7728



Beech Lister Larry J. reports that he removed 12 CB switches from his A36 in July 2009 and this is what his taxi and landing light breakers looked like:



Larry says: "they look good as new!"  I'm sure Larry is thrilled that he got them out of there before they melted down and let all the smoke out.........



web statistics