Pay By Tach and Save!
There are usually two time meters in the aircraft – tachometer and the Hobbs meter. The Hobbs meter is usually activated by either the engine oil pressure in single-engine airplanes or by a Master Switch in multi-engine aircraft. In either case, the Hobbs meter measures the engine's run time in human terms. It measures time in tenths of an hour. If you used the engine for 1 hour and 6 minutes, it will show it as 1.1 of an hour.
There’s also a Tachometer meter per each engine. It is activated only when the corresponding engine is started. The Tachometer measures the engine run time. Unlike in cars, it measure engine time in hours, not in miles. The intricacy of a Tachometer is that it depends on the engine speed. The faster the engine is running, the faster the time the Tachometer is measuring. That means that at idle power, the tachometer is slower than the Hobbs meter. At cruise power setting it is very close to the real time measured by the Hobbs meter.
Why does it matter to you as a pilot? Most of flight schools charge you by Hobbs. That means that when you are taxiing or sitting at idle power waiting for take-off, you are still charged by the Hobbs meter (real human time) even though you are not doing anything productive. In our company we charge by Tachometer. That means that on average you save between 0.2 to 0.3 hour (12 to 18 minutes) per flight. At current rates charged by other companies, that translates to about $50 per flight.
We realize that sometimes Republic airport can become as busy as JFK and wait times for take-off can approach 20 minutes. So why pay for that idle time? After all the engine doesn’t burn much fuel and you are not doing anything productive.
Fly with us, pay by tach, and save!