A “hot start” in any variant of a jet engine refers to the circumstance where the manufacturer defined limiting temperature for start has been exceeded. … The most common reasons for a hot start include insufficient airflow through the compressor, incorrect fuel scheduling and slow engine acceleration.
What is the difference between a hot start and a hung start?
A hot start is when temperature limitations are exceeded during start, possibly damaging the engine’s hot section. … Motor the engine long enough to purge all the fuel and hot gas from the combustor and allow airflow to cool the hot section. A hung start occurs when the engine starts but doesn’t accelerate to idle speed.
Will a hot start damage a turbine engine?
Exceeding temperature limits during a turbine start (a “hot start”) can cause severe engine damage requiring expensive repairs. … Reduced power assurance margins accompanied by high start temperatures may indicate a dirty compressor. Fuel control adjustments can also affect start temperature.
How do you know when your hung?
If the engine fails to accelerate to the proper speed after ignition or does not accelerate to idle r.p.m., a hung start has occurred.
How does a jet engine start?
Gas turbine engines come in many shapes and sizes. The electric motor spins the main shaft until there is enough air blowing through the compressor and the combustion chamber to light the engine. … Fuel starts flowing and an igniter similar to a spark plug ignites the fuel.
What is a jet fuel starter?
Jet fuel starter: This is also a gas-generating turbine, but unlike an APU, it does not function independently of the engines. The JFS is directly linked to the engine it is starting and can’t be used for any purpose other than starting the engine.
What is ITT temperature?
Interstage Turbine Temperature (ITT) is the temperature of the exhaust gases between the high pressure and the low pressure turbines. The gas temperature is measured by a number of thermocouples mounted in the exhaust stream and is presented on a flight deck gauge in either degrees Fahrenheit or degrees Celcius.
What is a hung stall?
Hung stall: after compressor stall, engine fails to recover immediately. Contexto. In-flight ice affects jet engines differently than reciprocating engines. For the most part, the problems involve damage to rotating components or disruption of the airflow through the engine and accompanying engine stalls or stagnations …
What is a hot start in a helicopter?
In an aircraft with a reciprocating fuel injected engine a hot start is a condition where an engine start is attempted after it has been run, achieved operating temperature, and then recently shut down. … Unlike a turbine engine, a hot start is unlikely to damage a reciprocating fuel injected engine.