ERJ climb profile difference Q

I've gotta say THE WORST captains I've flown with are the guys that explain to me how to fly the airplane the whole trip. I mean it doesn't matter the phase of flight, I'm ALWAYS doing something wrong. You marginalize your FO that way and after a day or two of this they stop paying attention to what's going on because they know that no matter what they do, the captain will tell them that they're doing it wrong.

I had a guy do that for a four day, and I couldn't want to get off that trip. He was easily one of the worst captains I've ever flown with. The worst was where we were trouble shooting a problem we were having with the plane on climb out. I took the plane and the radio's through about 10,000' and he goes to to call MX on number 2. He isn't listening to ATC this whole time, mind you. I start getting step climbs with speed restrictions so I start climbing at 250 knots from 14,000' to 15,000', and do it at VS 1,000' and partial power so I don't blow through the speed restriction. Jackass Jones in the left seat looks over at me (without knowing what ATC asked me to do), releases the trigger on the mic that he was talking with MX on and proceeds to chew me out about not knowing what I'm doing and how I should never climb with partial power or we'll stall.

Seriously?
 
Sounds like one of the lessons I've learned about CFI-ing. Often if you keep your mouth shut for just a minute longer the student will do what you were thinking. And if they don't, let them keep going anyway unless its a safety issue. They learn so much better if the screw up and have to work their way out of it than they do if you never let them make a mistake.

Exactly, Brotha! However, when you're 23, have never been in charge of anything, and you get that 4th stripe, some folks have trouble.
 
Of course I would always fly by our SOP's but in the off chance that safety of flight required me to do something slightly different than the SOP defined, here's what I might do:

Takeoff up until acceleration height (400' at most airports) would be SOP for sure. As soon as possible, accelerate to 240 or 245, depending on how smooth it is and climb in speed mode or FLC. Again, all of this is dependent on what the air is like that day.

Above 10,000', change to pitch mode and slowly pitch the plane down to around 3 degrees nose up. Generally that would end up being around 290kts to start with. You can pretty much keep this 3 degrees all the way up to FL370 but I would often back it off to a little less nose up to keep the speed up. I started off flying the plane and thinking pitch mode was dumb. After flying with a captain who had time in much larger aircraft and in the military, he taught me this method and I enjoyed it. It was simple and worked great in rough air and smooth air alike.

I haven't flown the plane (or any other plane for that matter) in around 6 months so my memory is a bit rusty but that's what I can remember. Again, this is what I would do IF I for some reason needed to venture away from SOP's.
 
Sorry to drag up an old topic, but this was something I spent some considerable time with at old of my old jobs.

I did extensive calculations from the performance manual, tested them online, and submitted the result to the company. It was several years worth of work. My results were the following:

For best fuel economy, in most conditions, climb at 270KIAS, then transition to .56 mach in the low twenties, and later transition to .65 mach in the upper twenties and maintain that.

In situations with a strong increasing headwind, a typical westbound climb into the jetstream, climb at 290/.65.

In all conditions, except a very strong increasing tailwind, climbs above FL250 should be on the .65 mach profile. So unless the wind starts picking up greatly after FL300, keep the speed up. .56 mach actually has a marginally higher fuel consumption above FL250 versus .65 mach.

LRC is about 250KIAS at all altitudes, with slightly higher speeds with headwinds in excess of 80kts. Simply slowing 20KIAS/.02M from high speed cruise will give you another 100-200 pounds of fuel at the destination, while adding a minute to the flight time, if that.

The book states that the most fuel efficient decent is idle at 290KIAS. That seems to be true, but an idle decent right to the crossing restriction is more important than 290KIAS. 11000/4.0 is faster and more fuel efficient than 11000/3.0 Holding low power settings in a decent also hurts fuel economy, so keep the power up and a shallow decent until you need to start down, then bring it to idle.

The best minimum clean speed is 4 degrees nose pitch up - speed will vary with weight. Anything slower, and the PPH will be higher than with flaps9. Basically getting behind the power curve, and flaps9 makes it plane out better.

4 degrees nose up is also a great climb profile. It will put the airplane on the 270/.56 profile, and slowly transition to .65 in the twenties. Stable, safe, and fuel efficient. Put the horizon line right through the middle of that notch on the bottom of the bird on the horizon, turn on the autopilot, and let it take you to level-off and cruise.

Unfortunately this operator really didn't care about fuel economy. Dispatch reliability was all important, with on-time departure coming in second. Fuel economy was only an afterthought.
 
Anybody got numbers for the 700?

When I flew the CRJ, most captains I flew with climbed out at 250 to 10k, 320/.79 and cruised at max cruise/cyan circle which gave us M.81-.82 at 370-410. Above 10k, 1500fpm to about 20k, then 1000fpm to FL320-340, 500fpm to FL370-410. It's probably not the most fuel efficient profile and most captains I flew with didn't care about fuel conservation. Dispatch usually filed us to cruise at .78/.79

Flying the ERJ-145, I found that 1000fpm at 10000, results in a 310kt/.70 climb all the way to the high 20s, then 500fpm around FL280-300 keeps the speed up around .68-.72 all the way to FL370. Filed cruise is .74/.75 Again this isn't the fuel efficient profile.

When I transitioned from the CRJ to the ERJ, I found the 270/.56 or even the 290/.65 profile uncomfortably slow personally, but I guess it's not unsafe.
 
Unfortunately this operator really didn't care about fuel economy. Dispatch reliability was all important, with on-time departure coming in second. Fuel economy was only an afterthought.

Interesting. My company experimented with "alternate climb profiles" several years ago.

These included 220 knots constant all the way to cruising altitude, 250/290/.56, the normal 240/290/.65(.60xr) and a few others I'm forgetting.

In the end they decided for whatever reason to stick with the established 240/290/.65(.60xr) pofiles. I think accomodating the better climbing aircraft that we share airspace with was a consideration. Flight idle descents are encouraged, although I find some resistance from pilots who still worry about things like "shock cooling" when making an idle descent all the way from FL370 to sea level.
 
I've gotta say THE WORST captains I've flown with are the guys that explain to me how to fly the airplane the whole trip. I mean it doesn't matter the phase of flight, I'm ALWAYS doing something wrong. You marginalize your FO that way and after a day or two of this they stop paying attention to what's going on because they know that no matter what they do, the captain will tell them that they're doing it wrong.

I had a guy do that for a four day, and I couldn't want to get off that trip. He was easily one of the worst captains I've ever flown with. The worst was where we were trouble shooting a problem we were having with the plane on climb out. I took the plane and the radio's through about 10,000' and he goes to to call MX on number 2. He isn't listening to ATC this whole time, mind you. I start getting step climbs with speed restrictions so I start climbing at 250 knots from 14,000' to 15,000', and do it at VS 1,000' and partial power so I don't blow through the speed restriction. Jackass Jones in the left seat looks over at me (without knowing what ATC asked me to do), releases the trigger on the mic that he was talking with MX on and proceeds to chew me out about not knowing what I'm doing and how I should never climb with partial power or we'll stall.

Seriously?

Betcha he wanted to show you the best way to do the DYLIN/PHLBO arrival, too! :D
 
You've flown with this guy too!?

:)

You mean 90% of IAH CAs?

After a while, my response to, "Has anyone shown you the best way to do the DYLIN?" was "Uh, make DYLIN at 8?"

Followed by, "Well, yeah, but..."

Me: "OK, go it."
 
You mean 90% of IAH CAs?

After a while, my response to, "Has anyone shown you the best way to do the DYLIN?" was "Uh, make DYLIN at 8?"

Followed by, "Well, yeah, but..."

Me: "OK, go it."

What was it again? 2.3 degrees and 1 dot high? Hehehehe.

I haven't flown the phlbo/dylin in about 2 years. Aren't most of the phlbo routes colgan/commutair now?
 
What was it again? 2.3 degrees and 1 dot high? Hehehehe.

I haven't flown the phlbo/dylin in about 2 years. Aren't most of the phlbo routes colgan/commutair now?

Not by a long stretch. Commutair I think does some EWR-IAD flights but that really didn't get you up high on the Phlbo arrival, usually we're only up at 16K-FL180.

Colgan does alot of Raleigh and some of the other small N. Carolina cities, I can't even keep them straight. But we're still on the Phlbo for all the JAX, SAV, RDU, GSP, GSO, BHM, ATL, Nassau etc flights.

As far as flying the Phlbo...the VNAV has at or above on all those waypoints where it appears, the first hard altitude you get is at Somto at 11. I don't see any reason why people wouldn't just fly at least a 3 deg or more and hit Somto at 11 flying over all those other waypoints.

Really though descent planning is poorly understood among many. I hear guys talk about having 10 minutes to a fix etc...When did time have to factor into things? Huh? Or times when the VNAV hasn't even appeared and guys hustle down...Huh?
 
I hear guys talk about having 10 minutes to a fix etc...When did time have to factor into things?

Lots of guys like to back up the FMS with a little mental math. I think using time is the easiest way to do a quick mental check. As an example, if I need to lose 10,000 feet and I know that around 2,000 - 2,500 FPM is a reasonable descent rate, then about 4 to 5 minutes away from the fix is where I should be expecting to see the VNAV pipper, eh?

Is that what you were asking?
 
I hear guys talk about having 10 minutes to a fix etc...When did time have to factor into things? Huh?
FWIW, I use time a lot for descent planning. As in, "lets see...ATC said cross YEAGR at 7000...we're at 12,000...that means at 1000 fpm, we need to start down when the GPS says 5 minutes to YEAGR." But I just fly little airplanes. Why doesn't this same method work in jets? Is it because they pick up mad speed when you drop the nose to descend?
 
I definitely use a combination of mental math and the VNAV bars. We're flying a jet aircraft, generally speaking we're looking for steep descents, not 1000fpm descents over long horizontal distances.

Generally what I see is guys who end up being low much earlier than they need to be. This leads me to believe they're not clear on descent planning. Being down 20 miles prior to a crossing restriction is typically not desirable.

Other scenario would be....let's say ATC left us high, both the FO and I realize it. Let's say we're at FL300 and have a restriction at FL200 and GS is 500 kts. So..simple math says 3deg is roughly 30miles needed at 2500FPM. If we're 25miles to go still at FL300, obviously we'll need greater than 2500fpm to make the fix. When I see guys put in this situation put in 2000fpm, then realize maybe that's not steep enough, then put in 2500fpm....then realizing they need more....etc....I'll speak up but it's clear they don't have a full grasp on the planning needed.
 
FWIW, I use time a lot for descent planning. As in, "lets see...ATC said cross YEAGR at 7000...we're at 12,000...that means at 1000 fpm, we need to start down when the GPS says 5 minutes to YEAGR." But I just fly little airplanes. Why doesn't this same method work in jets? Is it because they pick up mad speed when you drop the nose to descend?

No...we typically don't pick up much more speed in the descents, usually we're operating pretty close to our max speed (MMO) and actually we'll lose speed in the descents. Up at FL350 indication at .78M or roughly 250indicated we're doing 450kts TAS. As we descend into the teens indicated speed increases but our TAS will decrease. We're going slower.

I'd say in the jets you'll have wind play a much greater role. Going westbound in winter you may have a groundspeed of 300kts, while eastbound you may be doing 600kts. This affects your descent planning.

Also in jets you'll see a large difference between fuel flows up high and down low. In the teens you're going slow and using alot of gas to do so. This means ideally we stay high for longer and then come down "steep" with the power at idle. 1000fpm descents at least in the ERJ are not steep, requiring only a small power reduction.
 
Other scenario would be....let's say ATC left us high, both the FO and I realize it. Let's say we're at FL300 and have a restriction at FL200 and GS is 500 kts. So..simple math says 3deg is roughly 30miles needed at 2500FPM. If we're 25miles to go still at FL300, obviously we'll need greater than 2500fpm to make the fix. When I see guys put in this situation put in 2000fpm, then realize maybe that's not steep enough, then put in 2500fpm....then realizing they need more....etc....I'll speak up but it's clear they don't have a full grasp on the planning needed.

As another scenario to consider, I'll quite often put 2000 FPM in as a means to keep situational awareness. In the Lear (and Citation) around 2500 works for a pretty decent descent rate, and if I have 2000 in the VNAV the movement of the pipper lets me know that I'm getting close to wanting to start down. I don't have VNAV mode enabled, I'm just using the automation as a reminder. Many places that we go we might not have crossing restrictions (as on a SID), or I may not have been given a discretionary descent, so the 2000 FPM is a nice heads-up to query ATC if we aren't given a new altitude in the near future. In my case at least it doesn't have anything to do with not having a "full grasp on the planning." :)

I'd say in the jets you'll have wind play a much greater role. Going westbound in winter you may have a groundspeed of 300kts, while eastbound you may be doing 600kts. This affects your descent planning.

This has always struck me as a really good reason for using time rather than distance for VNAV planning. See my earlier post as an example. Which brings us full circle to why I originally commented on this part of your post:

Really though descent planning is poorly understood among many. I hear guys talk about having 10 minutes to a fix etc...When did time have to factor into things? Huh?

Time takes headwinds/tailwinds into account. 3 degree glideslopes don't. :)
 
3 deg is just an example...Depending on winds I'll use 4deg with a headwind or 3deg in a tailwind.

I can always calculate a vertical speed based on a 3deg. Increase it slightly for a 4 deg....

Also distance is more accessible information in most cases which leads to better situational awareness in other phases of flight. Could you tell if you're high when getting vectored based on time if you're not going directly to a point? For instance I can easily look on the moving map rings and see my distance to a FAF or airport and judge how my GP looks. When I'm going to Mexico at night, you better believe I'm not diving down to the lower altitudes, I'll stay high while maintaining descent clearances and knowing what distance is required to make the descents.
 
The G1000 is pretty good at giving you a WAG (wild arse guess) for time even if you're not being vectored direct to a fix, and that time is always displayed at the top of the MFD. If your FMS dealywhopper doesn't do that well, I can see why you'd rather use distance most of the time. Also I guess in our little, unpressurized planes we have to work to minimize descent rates...tends not to bother me, but the students always whine about their ears popping.

Like Steve said, I like using time in my little plane because it takes into account wind.
 
What was it again? 2.3 degrees and 1 dot high? Hehehehe.

I haven't flown the phlbo/dylin in about 2 years. Aren't most of the phlbo routes colgan/commutair now?

Something like that...

Actually, we still do a fair amount. I find myself on that arrival quite a bit, still.
 
I've noticed a big problem with descent planning at our airline, as Baronman mentioned. It's not really taught all that well. We have guys that start down way too early, especially when given a PD clearance. Then the guy behind you has to start down, etc. Also, while doing this, you're slowing down, which causes compression, which in turn causes the next 12 airplanes behind you to get slowed and turned off the arrival.
 
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