Inspection Items

Since returning from Thanksgiving, we have spent most of our time with Sis at her Moraine hangar. 

Picking up a LED shop light on Black Friday has been an early Christmas gift for us allowing us to more easily work into the evening.

Sis is a 1947 Beechcraft Bonanza model 35, one of the first 1000 off the assembly line. For all intents and purposes, she is my big sister as I have grown up flying with her and now am her caretaker.

Colder temperatures arriving reminded us winter was coming and gave a new sense of urgency. While we had a heater in the hangar at Moraine, we were using to supplement only when below 40 degrees. Dressing in layers and having hot beverages in a large thermos were keeping us motivated. Taking short breaks every hour or so for a few minutes helped to recharge and keep making progress.

There were some items the restorer needed to look over on Sis before signing off the annual.  As most of the areas have been inspected over the course of the year as parts of her rejuvenation, there were only a few others to look at to do a proper inspection.

Like the annual inspection on the clipped-wing Cub, the attention given to Sis’ annual inspection is backed up with reference material and manuals.

During the Cub annual inspection, the checklist containing inspection items from the manufacturer was on the restorer’s clipboard for continual reference during the process.  He mentioned the checklist provided by Beechcraft for Sis’ inspection is longer because she is a more complex airplane with additional systems.  

When we were up at Oshkosh, the restorer got a copy of the annual inspection guide from the American Bonanza Society and was reviewing that in addition to the information provided directly from Beechcraft.  

Looking at the checklist, I was impressed with how thorough it was at 99 pages.  Granted it is for more model years than just Sis’ 1947 referring to areas of difference by serial numbers or common upgrades.  

The restorer also found a copy of the original Beechcraft Bonanza Model 35 Maintenance manual.  He explained that the original maintenance manual provides plain language interpretation of the processes necessary to complete the inspection and gives insight into some areas the updated maintenance manual’s verbiage leaves out.

One item he mentioned from the original manual was the tie down procedure: using a tail stand in addition to two lines coming off from each tie down point. Certainly different from what is in use these days!

Wing Inspection

Panels underneath the wing are opened up to see the condition of cables attaching ailerons to the control wheel looking for frays or breakage.

The restorer is also on the lookout for corrosion as it must be remediated if found.

Different metals react differently to corrosion and if found on one type of metal, it should be treated and removed.

Greasing and Lubing of Tail and Gear

Like the Cub annual, Sis requires lubrication throughout the wings and tail using mainly LPS 2 with grease supplementing in some areas.

LPS 2 is applied to the cable pulleys and hinge points to lubricate.

A grease gun is used on fittings around the landing gear to flush new grease in. Near the tail and within the nose gear there are also areas. Before beginning the process, the restorer stressed it would be messy and to keep the shop towels coming.

The uplock rollers, while movement is checked as part of every preflight inspection, it’s during the annual or 100-hour inspection that the proper amount of lubricating agents is confirmed.

The visual inspection of the wing spar through the cabin supplements periodic non destructive testing done at a specialized shop like Poplar Grove Airmotive.

Flaps

Besides lubricating the aileron cable pulleys, attention was paid to the flaps which are also a part of the wing moved mechanically with the utilization of a flap switch in the cabin.

Before Sis’s unfortunate hiatus, her flaps were moving slowly. I brought this to the restorer’s attention and he was able to speed up the process by lubricating the system.

Brake Servicing

While the brakes were cleaned, inspected, and reinstalled, they still needed to be bled to ensure proper fluid was in the system.

The reservoir for the system is located inside the engine compartment on the firewall near the battery.  It is a small jar with a twist-on metal cap affixed with a sight gauge that sits inside the reservoir indicating the amount of fluid that sits inside. 

The restorer had a pressurized brake servicing pot and system for the Cub already and only needed a few parts for the different fittings on Sis.

Brakes require fluid within the system to work properly.  If there is a leak, fluid leaving the system will reduce the effectiveness as the fluid moves the bake calipers against the rotors.

The restorer said lots of shop towels would be used during this process as well as it can be a messy operation. I kept them close at hand and ready to pass as needed.

The restorer hooked the pot up to the brake lines on one of the main landing gear with me holding a bucket and overflow tube from the reservoir on the firewall.

His instructions were to hold the clear tubing into the bucket and let him know when fluid began to come out.  At first he said there may be bubbles with the fluid then straight fluid.  

One side done, then repeated the process on the other.

Once we confirmed fluid was in the reservoir from both mains, the restorer had me get into Sis to confirm brake feel on both sides.

While Sis was still up on the Beech jack, I was gettting more comfortable moving into and out of her cabin.

Making my way back into the left seat (Sis does not have brakes on the copilot side), I pressed my feet against the tops of both rudder pedals.  

Before long we will be flying again I said uncertain if I was reminding myself or Sis of this. 

There was resistance but it wasn’t like hitting a hard surface. Just what the restorer said we were looking for.

Upcoming Areas

Areas within the engine compartment still need to be addressed, but that will be another day.  Before flight, the restorer will also have the AD search done and signed off.  There are so many little things that need to be done, I have a new respect for maintenance professionals as they have to comply with necessary procedures which can be small and exacting.  

This process reminds me of the importance of breaking complex items down into smaller more manageable pieces – when a step-by-step process is laid out anything is possible.  As I’m writing this, some parts like writing the pieces are becoming easier but it’s still time and effort to make a quality piece.  Consistent effort repeated over time will produce results.  Patience and faith in the process is necessary.

The restorer has added an item to his checklist for Sis’ inspection: ensuring the stabilizer support casting is tight and torqued appropriately as part of each annual.

While we are ensuring she is in an airworthy condition now, she will be getting consitent improvements while staying in a predominatly flyable condition.