My plane did not come with shoulder harnesses. What do I have to do to install them?
If memory serves, the FAA mandated shoulder harnesses in new aircraft as of 1979, or somewhere around that timeframe. Beech began installing them as standard equipment earlier, in 1976, well before P and C began doing so. SB-2031 implies that the shoulder belts became standard as of serial numbers M1748 (C23) and MC386 (B24R), as the installation kits cover all the models and SN’s up to that point. Beech has one kit in stock as of November 2004, and it is priced at $1,993.51 (PN 23-5004-1). I have not verified this, but my understanding is that one kit covers two seats.
I have seen two styles of shoulder harnesses in the 19’s/23’s/24’s. The earlier style has the inertia reels mounted inboard of the pilot’s and co-pilot’s seats. You pull the belt up from the reel, across your chest, and it clips on an anchor point above your outboard shoulder. The later type (which I know was used as early as 1977, perhaps earlier), has the inertia reels mounted in the rear sidewalls. The belt runs up through a D-ring on the upper sidewall, then down across the chest, and clips on a pin on the seat belt buckle.
Unfortunately, both types require structural reinforcement at the anchor point on the upper sidewall. Beech Service Bulletin SB-2031 (EQUIPMENT/FURNISHINGS – NOTICE OF AVAILABILITY OF SHOULDER HARNESS KITS; downloadable from the BAC site, and probably elsewhere) spells out the details for kits. The actual modification instructions are
only in the kits themselves (not in the SB). The kit for the earlier planes has diagrams showing where to place the bracketry, and how to attach it. As is the case with the Bonanzas, these Beech kits were ridiculously expensive for what was in them.
The most practical solution, if you usually fly with the rear seats empty, is the system that attaches to the rear seat belts. Not very elegant, but better than nothing. Another possibility would be to find a salvage airframe with the Beech mod, and request a copy of the kit documents from Beech Tech Support; then transfer the applicable parts. With the Beech kit documentation this should not require an FAA field approval; the kit document will spell out the required maintenance log entry. The kit document might also (long chance) provide enough doc to go the “owner produced parts” route; sometimes they have sufficient detail on materials and hardware to enable reproduction of fabricated parts. If there is enough interest I can try getting some doc from Tech Support.
FWIW, I do think that a shoulder harness makes sense in light aircraft. In a great many cases the occupants survive an impact (such as a runway excursion on landing in strong winds, into a fence). But in the absence of a shoulder belt even a minor impact with an obstacle (5-10 MPH) results in the occupants being knocked unconscious. If the plane burns, they don’t make it out in time. Remaining conscious is critical for water ditchings as well. Most people don’t realize how slow a speed can result in serious head injuries, in the absence of a shoulder belt or helmet.
The Hooker Quickie Harness ($25 per seat)attaches to the rear seatbelts (for unoccupied seats), and are a viable option if you seldom fly with more than two occupants. They have received favorable mention from several owners. Make sure you understand how they work, and how they may or may not affect getting in and out of the seat, so that there are no surprises if you buy them. GARS also makes a similar system. Here are the two links: www.hookerharness.com; www.garsusa.com.
From John Rutkowski:
The Beech Service bulletin is SI 2031 Rev II. The needed kit is #23-5004-1. RAPID still shows the part, it was $1,200 the last time I
looked. Mechanic estimated about the same to get them installed.