LearJet 45 some questions

MCT means Maximum Continuous Thrust and is the point at which you can have the throttles set where the EGT won't exceed maximum parameters set in the POH/FM. It usually involves inputting the OAT into the FMC first. It is also the thrust setting to use in an engine-out situation.

As far as I remember, MCR is the Maximum Cruise Rating where thrust is set to maintain the maximum cruise speed. As fuel is burnt, thrust will increase to maintain a higher speed for a lighter weight. All of the thrust settings work with the input of the FMC.

Authothrottle can be engaged by engaging the A/T button. Sometimes, when I tried, it didn't engage, but you can just press IAS or something similar and it'll maintain the speed fine.

Touch brakes are probably the differential brakes above the rudder pedals.

😉

Excelsis wrote:

Hi
How do I activate autothrottle?

Any help gratefully received.
Thanks

I don't think there is an "A/T" button on the default Lear. As I recall, you dial in the speed you want into the little window with three digits to the right of of the Autopilot section, 250 is a good starting number if you're under 10,000 feet, then press the "KIAS" button (to the left of where you enter the speed) and it will start to work. Once you get up above about FL250, press the "Mach" button and the display will change to Mach number, and you can set it to what you want.

As long as either the KIAS or Mach buttons are lit, the A/T is engaged. To turn it off, click whichever button is lit.

Ed

99jolegg wrote:

MCT means Maximum Continuous Thrust and is the point at which you can have the throttles set where the EGT won't exceed maximum parameters set in the POH/FM. It usually involves inputting the OAT into the FMC first. It is also the thrust setting to use in an engine-out situation.

Thank you very much! But oh these acronyms, endemic in the world of aviation! OK, I have EGT = Exhaust Gas Temperature and FMC = Flight Management Computer.

But POH? FM? OAT?

Can you also enlighten on these?

Thanks!

Maximum Cruise thrust (MCR)
Sometimes defined, but not a particularly useful rating since in cruise the pilot/autopilot will use the thrust required to maintain constant altitude and air speed to meet with air traffic control requirements.

Maximum Continuous thrust (MCT)
Outside the MTO flight envelope, the MCT rating defines the maximum thrust that can be demanded by the pilot from the engine. As such, it has particular significance with respect to engine failure in flight, as the aircraft will have to proceed to its destination or nearest diversion airport at max continuous thrust. If the engine cannot achieve this thrust level whilst staying within it operating limits for engine speed and temperature, (them 'amber line'), it is no longer considered airworthy.

➡ http://en.wikibooks.org/wiki/Jet_Propulsion/Engine_ratings

Auto throttles- as stated above by guest Ed

"Touch brakes"- This is a reference in the checklist to hit the toe brakes to stop main landing gear wheel rotation after takeoff. This prevents the fast spinning, and somewhat distorted wheels, from scrubbing in close fitting wheel wells during gear retraction(not necessary in FS).

POH- Pilot Operating Handbook
FM- Flight Manual
OAT- Outside Air Temperature

Thanks all of you. Am now enlightened!

Excelsis wrote:

99jolegg wrote:

MCT means Maximum Continuous Thrust and is the point at which you can have the throttles set where the EGT won't exceed maximum parameters set in the POH/FM. It usually involves inputting the OAT into the FMC first. It is also the thrust setting to use in an engine-out situation.

Thank you very much! But oh these acronyms, endemic in the world of aviation! OK, I have EGT = Exhaust Gas Temperature and FMC = Flight Management Computer.

But POH? FM? OAT?

Can you also enlighten on these?

Thanks!

POH = Pilots Operating Handbook
FM = Flight Management Computer
OAT = Outside Air Temperature

JHTaylorJr wrote:

POH = Pilots Operating Handbook
FM = Flight Management Computer
OAT = Outside Air Temperature

Just to let you know this post is a year old, it is worthless 😉

PS: Welcome ❗ 😀