What’s the story on the part numbers for the spar covers? This is the part that covers the spar carry-through splice, just forward of the 3rd/4th seats, beneath the passengers’ legs. Some seem to be plastic, while others are metal. Some of the metal ones have fabric or carpet on them. Who sells these things?
Below is a part number breakdown for all the spar covers.
Vantage Plane Plastics (formerly Kinzie) sells the plastic style, used on the Model 19/23/24 planes through 1977. As is so often the case, the aftermarket part is show under the assembly number rather than the actual part-only number; the Kinzie part does not come with any hardware, but little is needed. The part image also has the wrong orientation; it is not illustrated as it is placed in the plane. The Kinzie part also does not come with openings for the rear floor heater outlets, if your plane is so equipped, but it is easy to adapt. The Kinzie part seems to be at least as good as the original ABS part, but may require some minor fitting.
Only Beech lists the metal versions, and they have no stock (with one exception as noted). However, the metal versions rarely require replacement, and could (fairly easily) be field-fabricated as an owner-produced part. If anyone wants me to try to get the 169-534121-5 metal cover, let me know. These sub-assemblies often are not reflected in parts lists and online searches/ordering, as they were production parts rather than replacement parts. Most people, other than old Beechers, don’t even know that they exist.
A.) Spar cover assembly P/N 169-534017-17 is set up but no stock. The -17 assembly is a 169-534017-5 spar cover with several MS 27980-1N, -6N, -7N, and -8N fasteners installed. The -5 spar cover is manufactured from 125 ABS Thermoplastic.
***This is the black ABS plastic cover that was used on all the 19/23/24 production up through 1977. This included M0001 1979, MA001-368 (all the MA-prefixed airframes), MB001-865, and MC002-536.
B). Spar cover assembly P/N 169-534121-3 is set up but no stock. The -3 assembly is a 169-534121-5 spar cover with Grospoint carpet. The -5 is manufactured from .025 aluminum alloy and RAPID has five (5) of the -5 in stock. Note that Spar cover assembly P/N 169-534121-3 does not supersede spar cover assembly P/N 169-534017-17; there are no supersedures.
***This was used on the 19/23/24 models, M1980 through M2233, MB866 and after, and MC537 through MC701.
C). Spar cover assembly P/N 169-534121-29 is set up but no stock. The -29 assembly is a -27 cover and 2 each -25 tubes. The -27 is manufactured from .025 aluminum alloy.
***This was used on the C23’s, M2297 and after.
D). Spar cover assembly P/N 169-534121-15 & -33, were for aircraft with 5th and 6th seats installation. The -15 spar cover assembly use the -5 spar cover and the -33 spar cover assembly use a -29 spar cover. Also the -13 spar cover assembly uses the -5 spar cover and the -13 is set up in the old computer system but the -15 is not, neither the -13 or -15 spar cover assemblies are set up in the new computer system.
***The dash 15 was used on Sierras MC689, 702 through 745. The dash 33 was used on Sierras MC746 and after.