ERJ-170/190 autothrottles

[aa73]

Just an observation, more out of curiosity than anything else: do the autothrottles "hunt" a lot during approach and landing? and are you guys allowed to disconnect them on approach? i ask b/c i've flown aircraft where they do hunt a lot, and I always disconnected them and kept the power as constant as possible.

 

[LearLove]

yes they suck (although I have nothing to compare it to, see my profile) for some reason setting the speed bug 5 knots above adjusted Vapp in gusty winds seems to hold the airspeed at Vapp. Hand flying with AT off use about 50% N1 and you will be fine.

Another note: I hear a lot of remarks about the 170/190 being a POS built in Brazil but everything that is a POS on the jet was designed and built in the US. Example the cockpit seats (Seattle, WA), the Honeywell FMS Software (PHX, AZ), the uber POS printer and the ACARS - where the F' is it gonna hide the message today?

 

[lowlycfi]

Agreed, they tend to hunt in gusty winds. Anything over about 5 knots of wind, I turn 'em off. Overriding them works ok too, but as Lear said setting about 50% and fine tuning from there works well. I hate sitting in the back and listening to the engines spool up and down all the way down final.

 

[DYLIN]

Just an observation, more out of curiosity than anything else: do the autothrottles "hunt" a lot during approach and landing? and are you guys allowed to disconnect them on approach? i ask b/c i've flown aircraft where they do hunt a lot, and I always disconnected them and kept the power as constant as possible.

I just barely remember them doing those things.

I can't remember well because I haven't landed with them on in two years.

Why override a system when you can turn it off!

Technically, they violate my company's stable approach criteria because they'd occasionally go all the way to idle . . . because we're . . . 6 knots fast.

 

[Headfake14]

I'd say that sometimes they are a little over reactive. I think it's because the airspeed info is so precise it micromanages the $hit out of the speed.

In gusty winds, I almost always turn them off. You can feel when a gust hits or drops off or you get a down draft...and you ALWAYS react quicker then the auto throttles could. I'd say they're no worse than the maddog from what I've seen on the J/S and talking shop with those guys.

Some guys will 'override' them because in the event of a missed approach, they'll already be on and you wouldn't have to worry about having to re-engage them.

other news...

Yea...Honeywell as dropped the turd bomb on themselves with the FMS and printer. The printer is jacked up because of Honeywell. Some line of code in one of the original software loads. They are working on it.

Seats...WTF. The CRJ's seats (with the big headrest) are better than what we have.

 

[Axel]

The throttles do hunt in gusty conditions but it doesn't get out of hand. It can be annoying, though.

I have seen pilots get into a divergent oscillation in speed by overriding the AT. I have seen that get out of hand.

 

[248to2.8]

Same here, I usually turn it off in gusty winds. The 717's AT also did the exact same thing, so I don't know if its an auto throttle issue, or an airplane specific issue.

 

[Flying Illini]

The A/T's used to be far worse before a software upgrade came out (several updates ago). As it is now, they will occasionally hunt but it's easy enough over-ride them and even easier to just turn them off.

As said before, very gusty winds cause problems.

 

[rogerwilcoout]

What sucks worse is the "Ice Speeds". As the aircraft encounters ice, even though it was a lone cloud that gave you the brief encounter with light rime, the EICAS will get a ice speed message. Sooooooo, even though you are landing in 90 degree heat in Orlando, you have to adjust your speeds to ice speeds. This is because the engineers decided to not put anti ice systems on the tail. Not a big deal for the most part until you need to land in Key west or DCA. Then it is flaps full.

 

[DGdaPilot]

What sucks worse is the "Ice Speeds". As the aircraft encounters ice, even though it was a lone cloud that gave you the brief encounter with light rime, the EICAS will get a ice speed message. Sooooooo, even though you are landing in 90 degree heat in Orlando, you have to adjust your speeds to ice speeds. This is because the engineers decided to not put anti ice systems on the tail. Not a big deal for the most part until you need to land in Key west or DCA. Then it is flaps full.

WTF? The CRJ has no ice protection on the tail and doesn't use "ice speeds."

 

[Flying Illini]

What sucks worse is the "Ice Speeds". As the aircraft encounters ice, even though it was a lone cloud that gave you the brief encounter with light rime, the EICAS will get a ice speed message. Sooooooo, even though you are landing in 90 degree heat in Orlando, you have to adjust your speeds to ice speeds. This is because the engineers decided to not put anti ice systems on the tail. Not a big deal for the most part until you need to land in Key west or DCA. Then it is flaps full.

It has nothing to do with a non de-iced/anti-iced tail.

 

[aa73]

Thanks guys. Guess it's a common problem on all aircraft in gusty winds. I especially noticed it while hanging out at Gravelly Point (park just off the end of DCA Runway 19) watching a USAir Express 170 on final... just rolling out from the last turn, the engines just went up, down, up, down all the way to the flare. And it wasn't gusty at all. I either figured the crew was stabilizing or the autothrottles sucked.

 

[rogerwilcoout]

It has nothing to do with a non de-iced/anti-iced tail.

Yes it does

 

[Flying Illini]

Yes it does

No, not really. Otherwise every other a/c I've flown without a deiced tail would be required to use ice-speeds after an encounter with icing. Add to that every a/c out there that I haven't flown that doesn't have a de-iced/anti-iced tail (see above posting about the CRJ). That's not the case. It does have to do with Embraer not going a little further in their certification efforts thus the latched "ice" message and the requirement for ice speeds.

 

[SpauldingSmails]

Thanks guys. Guess it's a common problem on all aircraft in gusty winds. I especially noticed it while hanging out at Gravelly Point (park just off the end of DCA Runway 19) watching a USAir Express 170 on final... just rolling out from the last turn, the engines just went up, down, up, down all the way to the flare. And it wasn't gusty at all. I either figured the crew was stabilizing or the autothrottles sucked.

Yeah, the autothrottle system on the e-jet is definitely the "D student" of autothrottles. Not only do they hunt in gusty conditions, they tend to error to the low-side of Vap and slower, as opposed to varying at Vap to a somewhat higher speed. Its not very comfortable, so its best with the A/T off in gusty conditions.

They generally tend to lag, then over correct which creates a lot of nice cabin bumps at altitude when making speed changes if you don't help them.

Likewise, the aircraft is much easier to land with smoothness and precision with the A/T disengaged when landing flaps full.

 

[WMUSIGPI]

Yeah, the autothrottle system on the e-jet is definitely the "D student" of autothrottles. Not only do they hunt in gusty conditions, they tend to error to the low-side of Vap and slower, as opposed to varying at Vap to a somewhat higher speed. Its not very comfortable, so its best with the A/T off in gusty conditions.

They generally tend to lag, then over correct which creates a lot of nice cabin bumps at altitude when making speed changes if you don't help them.

Likewise, the aircraft is much easier to land with smoothness and precision with the A/T disengaged when landing flaps full.

The CRJ, what autothrottles, nuff said.
The Avro , it was rock solid for the most part. Procedure was for us to land with them shut off because we didn't have FAA authority for Cat III autoland (though it could do 3A no problem)

 

[DrewBlows]

The auto-throttle on the embraer hold speed better than most pilots in my opiniono. They move a bit, but the biggest problem I've seen with them are pilots comfort level. A lot of guys can't stand to see them move and disconnect them or override them without ever giving them a chance. I've never seen autothrottles go wildly off speed, I can't say that for pilots. That's not to say I don't cover them to see what they are doing, but I wouldn't trade them for a non-auto throttle system.

 

[Popeye0537]

170 auto throttles with gusty winds = not good
190 auto throttles with gusty winds = not to shabby

Ice speeds make for a nice smooth landing with the extra 10 knots....and please STOP overriding the throttles when they are at flight idle! Flight idle is NOT ground idle, the throttles sit forward of the stop detent in auto mode.