Why is spray pattern check important during PM?

• A. To ensure proper atomization and spray distribution
• B. To measure fuel filter DP
• C. To check oil viscosity
• D. To adjust ITT

Answer: (A)

spray pattern check matters because it directly ensures the fuel is atomized properly and spread evenly by the nozzles. When atomization is good and the spray covers the intended area, fuel droplets mix with air effectively, leading to stable, complete combustion. This improves ignition reliability, keeps temperatures more uniform, reduces emissions, and helps prevent flameout or hot spots in the combustor. If the spray pattern is off, you can get uneven burning, higher hydrocarbons and soot, and potential performance problems as the engine runs.

The other items don’t address how the fuel is delivered and burned. Measuring fuel filter differential pressure checks filter condition, not how the spray actually disperses fuel. Checking oil viscosity relates to lubrication, not combustion spray. Adjusting ITT is a control parameter or test of engine operation, not a PM check of fuel spray distribution.