The assembly of a glider to include the installation of glider wings and tail surfaces is classified as operations functions not preventative maintenance. This information can be found in Amendment 43-27, published in 52 FR 17276, May 6, 1987 which is an amendment to 14 CFR part 43. Prior to assembling the glider, the pilot must check the required documentation that must be on board the glider for flight as required by Title 14 of the Code of Federal regulations (14 CFR) parts 21 and 91. Required documentation includes:
- Airworthiness certificate
- Required placards
While preparing to assemble a glider, consider the following elements: location, number of crewmembers, tools and parts necessary, and checklists that detail the appropriate assembly procedures. Glider pilots should also develop and follow a procedure, or procedures, to deal with distractions that may occur during the glider assembly. Something as simple as rechecking the previous two steps and then continuing the checklist steps might be sufficient. The GFM/POH should contain checklists for assembling and preflighting a glider. If not, develop one and follow it every flight. Haphazard assembly and preflight procedures can lead to unsafe conditions.
Before assembling a glider, ensure that the glider trailer is secured with the wheel brake on and the wheels chocked. Adjust the leveling of the trailer as needed according to the GFM/POH so the glider can be removed without damaging items, such as the antenna and other glider components (e.g., wings, tips, horizontal elevator). If using a single rigging device, ensure that the wing holder is adjusted so the wing does not slide out of the holder and become damaged by striking or falling to the ground.
Find a location that shields the project from the elements and offers enough room for completion. Wind is an important factor to consider during an outdoor assembly. Each wing is an airfoil whether or not it is connected to the fuselage; even a gentle breeze is enough to produce lift on the wings, making them cumbersome or impossible to handle. If assembling the glider in a spot unshielded from the wind, great care must still be taken when handling the wings.
When performing the assembly inside a hangar, ensure there is enough room to maneuver the glider’s components throughout the process. Also, consider the length of time anticipated to complete the entire procedure, and choose an area that allows complete undisturbed assembly. Moving the glider during assembly may cause parts or tools to be misplaced.
Wing stands or a wing dolly, the proper tools, wing tape, and lubricants should be on hand when assembling the glider. [Figure 6-1] To stay organized, use a written assembly checklist, and keep an inventory of parts and tools. Some organizations track tools and components by placing all of the necessary components and hardware used with necessary tools on a piece of canvas or material and outlining each tool. This facilitates a quick inventory before assembly and afterwards. Once glider assembly is complete, pilots should account for all parts and tools used during assembly. Objects inadvertently misplaced in the glider could become jammed in the flight controls, making control difficult, if not impossible. In addition, when taping the wing roots, turtle deck (cover where the flight controls are attached) elevator and other areas, ensure the tape is placed properly and is secure. If the seal tape comes off in flight, the tape may cause control issues with the glider.
Depending on the type of glider, two or more people may be required for assembly. It is important for everyone involved to maintain focus throughout the assembly process to avoid missed steps. Outside disturbances should also be avoided. Once the assembly is finished, a thorough inspection of all attach points ensures that bolts and pins were installed and secured properly. Do not use a hammer to tap wing bolts or other glider components in their place. The main wing pins should slide into the socket with minimum application of force. If the wing bolts require such force, a mechanic should be retained to ensure that the main wing spar is not bent or damaged.
On most gliders, the wing can be completely removed from the fuselage area. On some motor gliders, the wing can be folded up for ease of storage. [Figures 6-2] This allows the glider to be placed in a normal size hangar. Hangars are usually between 35 and 45 feet in width. Because most glider wings are a minimum of 40 feet (12 meters) total length, a larger hangar is usually desirable.
Once the gliders wings have been folded, the glider can easily be moved in and around the hangar area. On some gliders, operators may elect to leave the wings attached for quick access. This is usually the practice at larger glider operations. These gliders can be fitted or rolled onto a small dolly that has castering wheels. The glider’s main wheel fits into a slot, and the entire glider can be pivoted and moved to accommodate other gliders.
Once the glider has been completely assembled, the pilot then inspects all critical areas to ensure all flight controls are attached. The pilot should refer to a written checklist either provided by the manufacturer or a commercial source that prints glider checklists.
This final check is very critical and usually takes time to complete. Pilots should not be interrupted when they are attempting to check the glider. The Soaring Society of America (SSA) and one of its affiliates, the Soaring Safety Foundation (SSF), have developed a checklist for preparing a glider, which is Safety Advisory 00-1, Glider Critical Assembly Procedures, and can be found in Appendix A of this handbook.
Many manufacturers provide a critical assembly checklist (CAC) to be completed after assembly, which is the preferred method of ensuring a proper assembly has been completed. When provided by the manufacturer, it is mandatory. A positive control check (PCC) is not a CAC, but an additional means of verification. If a CAC is provided, it must be used as is any other checklist a manufacturer provides. A PCC is not regulatory, but it is a good idea whether or not you just completed the required CAC.
Specially designed trailers are used to transport, store, and retrieve gliders. [Figure 6-3] The components of the glider should fit snugly without being forced, be guarded against chafing, and be well secured within the trailer. Once the loading is completed, take a short drive, stop, and check for rubbing or chafing of components. Ensure that any items carried inside the trailer are secure from movement. For example, jacks, ramps, wing stands, and ground dollies must be secured so that these items do not damage the glider.
Prior to taking the trailer on the road, complete a thorough inspection. Ensure:
- Proper inflation of and adequate tread on trailer tires,
- Trailer tires are rated for Special Trailer (ST) duty, which are rated only to 65 miles per hour (mph) towing speed. The maximum speed of 65 mph can be exceeded safely if the air pressure is increased by 10 psi for every 10 mph over 65 that it is pulled and the maximum load is decreased 10 percent for every 10 mph over 65 mph of towing speed,
- Operation of all lights,
- Free movement and lubrication of hitch,
- Appropriate rating of vehicle attachment for the weight of the trailer,
- Proper operation of vehicle and trailer brakes,
- Adequate wheel bearing lubrication, and
- Proper tow vehicle mirror adjustment.
When using a trailer, there are other precautions to note. First, avoid towing with too much or too little tongue weight as either causes the trailer to fishtail at certain speeds, possibly rendering it uncontrollable. Towing a long glider trailer requires good driving skills and a good sense of road and weather conditions. Take care in heavy crosswinds because a long trailer can be affected by windy conditions. Also, take care when unloading the glider to avoid damage. Practice and planning are key to a successful operation.