"Mandatory" Service Bulletins and Letters. Many aircraft manufacturers issue Service Bulletins (SB) and Service Letters (SL) containing the word "mandatory". Since balloon operations are conducted under part 91, manufacturer SBs and SLs have no regulatory backing, therefore, completion of procedures recommended therein is not required by federal law.
Most aircraft owners choose to comply with SBs and SLs as they are usually issued to correct a problem or improve safety. Sometimes, however, when the manufacturer expects the owner to pay for the procedure, there may be a cost factor which may deter an owner from complying. The owner has the right to refuse.
SBs and SLs that are referenced in an Airworthiness Directive (AD) or the Type Certificate Data Sheet are regulatory and must be complied with for airworthiness.
The FAA has no official stand on SB and SL compliance under Part 91. In interviews with FAA inspectors in four different offices we got three different viewpoints. One inspector felt all SBs and SLs should be complied with because they make an aircraft safer and better. Another felt that many SBs and SLs (also some ADs) were issued foolishly and that the use of the term "mandatory" in a SB or SL is ridiculous. A third said that in at least one case the FAA advised a manufacturer that if they felt a particular procedure "mandated" that a SB be "mandatory" for safety, they should ask the FAA to issue an AD.
Most SBs and SLs make sensible recommendations. If one is issued against your balloon, discuss it with your balloon repair person.
Gauges. Instruments, and Avionics. Many people in ballooning misunderstand the correct definition for gauges, instruments, and avionics.
A gauge measures an amount, rate, or degree. Gauges on balloons measure fuel pressure, percentage of fuel remaining, and envelope temperature.
An instrument is a device using an internal mechanism to indicate visually or aurally the attitude, altitude, or operation of an aircraft or aircraft part. Instruments in a balloon are rate-of-climb (also called vertical speed indicator), and altimeter.
The term avionics is less clearly defined, but is generally understood to include identification and communications equipment such as radios and transponders, and navigational equipment such V.O.R.s, Loran, and GPS. No avionics are required equipment in balloons.
Since balloon manufacturers don't always understand the difference between gauges, instruments, and avionics, it behooves owners to know which is which. One manufacturer, for example, states their digital temperature indicator (which is a gauge) should be recalibrated by a certified avionics mechanic.
Balloon repair facilities may repair, adjust, install, remove, replace, and calibrate gauges. Instruments and avionics must be repaired by appropriately-certificated facilities, and avionics must be installed by an FAA-certificated radio shop.
Acceptable and Approved. the FAA makes a distinction between acceptable and approved data used for major and minor repairs. Data, to the FAA, can be instructions, drawings, pictures, photos used to "describe" a Type Certificate product, such as manufacturers' engineering drawings or alterations to Type-Certificated products such as an STC. Data can also be instructions to maintain a product, such as a manufacturer's maintenance manual.
Acceptable data may be used for minor repairs, and approved data must be used for major repairs and alterations. Approved data can be used in place of acceptable data, but not vice versa.
Some data considered acceptable to the FAA are manufacturers' maintenance manuals and manufacturers' service bulletins.
Data considered approved by the FAA are Type Certificate Data; Supplemental Type Certificate data; Airworthiness Directives; Designated Engineering Representative data; Designated Alterations Station data; Appliance manufacturers' manuals; Anything stamped "FAA-approved".
Most balloon repairs can be done according to the manufacturers' maintenance manuals (instructions for continued airworthiness), or repair station manuals, which are acceptable data.
Elsewhere in this issue of BALLOON LIFE you will find a survey conducted by the Balloon Repair and Maintenance Association (BRMA), which will help the association advise the FAA regarding revision of Federal Aviation Regulations governing balloon repair. We ask that you take the time to complete the survey so that all balloonists are represented.