Fuel Freeze Point Investigations.
Abstract
The objective of this program was to conduct a detailed assessment of the low temperature environment to which USAF aircraft are exposed for the purpose of defining a maximum acceptable fuel freeze point and also to define any operational changes required with the use of a high freeze point fuel. A previous study of B-52, C-141, and KC-135 operational missions indicated that the -58 C freeze point specification was too conservative. Based on recommendations resulting from the previous program, several improvements in the method of analysis were made, such as: expansion of the atmospheric temperature data base, the addition of ground temperature analysis, the addition of fuel freezing analysis to the one-dimensional fuel temperature computer program, and the examination of heat transfer in external fuel tanks, such as pylon or tip tanks. The B-52, C-141, and KC-135 mission were analyzed again, along with the operational missions of two tactical airplanes, the A-10 and F-15; -50C was determined to be the maximum allowable freeze point for a general purpose USAF aviation turbine fuel. Higher freeze points can be tolerated if the probability of operational interference is acceptably low or if operational changes can be made. Study of atmospheric temperatures encountered for the missions of the five study aircraft indicates that a maximum freeze point of -48 C would not likely create any operational difficulties in Northern Europe. Originator-supplied keywords include: freeze point, fuel tanks, holdup, Tables(Data), Graphs.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1984
- Accession Number
- ADA152801
Entities
People
- F. F. Tolle
- L. A. Desmarais
Organizations
- Boeing Military Aircraft