Summary
We propose to adopt a new airworthiness directive (AD) for all Fokker Services B.V. Model F.28 Mark 0070 and 0100 airplanes. This proposed AD was prompted by a design review which revealed the absence of electrical insulation material between a wing or integral center wing tank (ICWT) fuel quantity indication system (FQIS) probe and the bottom of the tank structure. This condition, if not corrected, could, under certain conditions, result in an ignition source in the tank vapor space, which could result in a fuel tank explosion and consequent loss of the airplane. This proposed AD would require, for all airplanes, applying sealant below the FQIS probes in the wing tanks; and for certain airplanes, applying sealant below the FQIS probes in the ICWT. This proposed AD would also require revising the aircraft maintenance program by revising the fuel airworthiness limitations and incorporating critical design configuration control limitations (CDCCLs). We are proposing this AD to prevent an ignition source in the tank vapor space, which could result in a fuel tank explosion and consequent loss of the airplane.