RJ's and autothrust

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01-26-2008, 11:08 PM

#21

Senior Skipper

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I only get the triple feature ones

01-27-2008, 03:53 AM

#22

overspeed

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Quote:

Originally Posted by Senior Skipper

How do you go about power management anyway? Do you chase a specific speed/mach, or do you just set a specific power setting and take the speed you get?

When you're starting out, you basically have to guess at a power setting that will give you the speed you're supposed to fly. After a while, it becomes intuitive. Watch the captains you fly with. Mimic the ones that do it well.

01-27-2008, 05:09 AM

#23

POPA

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Quote:

Originally Posted by Senior Skipper

Never seen one that will takeoff on it's own.

I've flown lots of planes that will take off on their own - even a 172! You just have to set the trim correctly.

01-27-2008, 05:45 AM

#24

145Driver

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In the 145 the detent is a great place to start with a power setting, but seems like you have to pull it back a lot of times to keep b*****n' Betty quiet...

01-27-2008, 06:57 AM

#25

flynavyj

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thats cause the 145 has those poor man auto throtle, aka, a power mode button, keep it in the detent, press the cruise button, engines roll back then pull it back a lil to keep betty quiet.

01-27-2008, 07:13 AM

#26

BoilerUP

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Why don't RJs have autothrottles?

COST.

01-27-2008, 08:02 AM

#27

nicholasblonde

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My Uncle is a SWA captain, and he said company policy forbids them from using autothrottles when installed.

01-27-2008, 08:11 AM

#28

nicholasblonde

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Also...I wouldn't use autothrottles even if they were available on everything...because I'm eventually gunning for a couple of ACMI jobs on some old old freighters, and those things require a pretty good feel for how a turbine responds to power inputs...I can't imagine starting out a career in a E170, and never having to become fully in touch with the relationship between throttle inputs and engine response. I guess it's not that huge of a deal, but still, the plane navigates itself, the least you can do is get a feel for how to manage your thrust.

01-27-2008, 08:17 AM

#29

freezingflyboy

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Quote:

Originally Posted by Senior Skipper

Take it easy there. I'm not attacking you. Not saying that RJ's are lesser planes, but just wondering why this "simple" functionality seems to be absent.

I'm not concerned about you "attacking" me nor do I think you are and the RJs ARE lesser planes. But that "simple" system you refer to is actually rather complex and costly and really not of a huge benefit on an aircraft designed to fly relatively short legs. Autothrottle's pay for themselves on the longer legs where they can more accurately hold a speed and more smoothly adjust the power, which saves fuel by eliminating the more significant and less accurate power changes that come from human inputs. They are not designed to be a "cruise control" or crutch to free up time for the pilots to do more important things on the flightdeck (like sudokus and crosswords).

01-27-2008, 08:27 AM

#30

SharkyBN584

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Quote:

Originally Posted by overspeed

Don't know if this works on the CRJ, but for the 145 if you're looking for a specific speed, just halve the the airspeed, add a zero, and set that as your fuel flow.

Example: You're level at 8K cruising along and trying to maintain 250 knots. Set the thrust levers so each fuel flow reads 1250 pph (250/2=125 then add the zero). If you wanted to maintain 210 knots, use 1050 pph.

It works at all altitudes, but it's more accurate at lower altitudes (say, below 15K). Also, when you descend, if you want to maintain that speed, drop the power 400pph for each 1,000fpm (i.e. for a 1500fpm descent, drop the power back 600pph). You'll have to bump the thrust levers forward as you descend though to maintain that fuel flow. Takes a lot of the "guesswork" out of it though.