CRJ-200 Summer Climb Techniques

GaTechKid

GaTechKid

Well-Known Member
Last week was my first week on the -200 when it was as hot as ISA+16 and the climb/cruise performance was shocking. Our fuel conservation climb profile of 250/.70 leaves you hanging on the engines at high altitudes when you're hot and heavy. What do you other CR2 drivers use when the temps get past ISA+10ish?
 
GaTechKid said:
Last week was my first week on the -200 when it was as hot as ISA+16 and the climb/cruise performance was shocking. Our fuel conservation climb profile of 250/.70 leaves you hanging on the engines at high altitudes when you're hot and heavy. What do you other CR2 drivers use when the temps get past ISA+10ish?
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I am concerned that this was not taught to you in ground school, or that a captain has not taught you this. The reason for the 250/.70 (I thought it was 180/.70, but it has been a while), is not just fuel conservation, but for thrust for the engines. Turbo fan engines need airflow to develop power; if you get below the cruise climb airspeeds you really are not gaining anything- the short term gain is more than offset by the thrust you loose as airflow into the engines decreases.
Also, if you are using these airspeeds but not getting a climb rate, you need to stop you climb. You are probably getting into the coffin corner. Continuing to climb will lead to this:
http://ntsb.gov/ntsb/brief.asp?ev_id=20041015X01633&key=1
 
The best I have found is a middle of the road approach between saving fuel and keeping to mo' going.

Basically 250 kts to FL200 - then push the nose over and fly the normal 290 - .70M. Works like a charm. This thing dogs out at 250 knots as you have seen.

Blackhawk you are close on part of the reason, these engines need air since they are indeed high bypass, but a big part is that the swept wing needs speed to develop good lift. The CRJ doesn't like to fly slow at all with those two factors.
 
bike21 said:
The best I have found is a middle of the road approach between saving fuel and keeping to mo' going.

Basically 250 kts to FL200 - then push the nose over and fly the normal 290 - .70M. Works like a charm. This thing dogs out at 250 knots as you have seen.

Blackhawk you are close on part of the reason, these engines need air since they are indeed high bypass, but a big part is that the swept wing needs speed to develop good lift. The CRJ doesn't like to fly slow at all with those two factors.
Click to expand...

I'll have to wait until I can look at my old manual (it's in my closet and wife's asleep), but there used to be a memo at my old airline about staying on speed and not slowing down as the engines actually lost quite a bit of thrust. Probably a combination of the two.
Still, I am very concerned that we have pilots flying around in CRJs who do not understand that you can climb right into the coffin corner, especially in the summer. This is NOT a FL410 airplane in the summer. I figured after the Pinnacle crash this was being beaten into all new hires. Makes me REAL nervous about putting my kids on one with a couple "dudes" up front.
 
I know what you are saying - I don't like the 'dude' factor either. However, let GaTechKid answer for himself. He has been around awhile and isn't one of those 'dudes' as far as I know.

I think he was asking about technique vs. pushing it to the brink of problems. Our fuel conservation profile calls for 250 kts all the way up to about FL320 which is somewhere around .70M. Well, that only works in certain conditions. SOP is only good as common sense. Same thing with our fuel conservation climb to 10,000', we are supposed to be a 200 knots. Again, common sense prevails when icing conditions exist and we should speed up to >230 knots so we don't need the wing a/ice on and don't have the extra power sucked away.

Point being, the guys who follow SOP to letter scare me too. Thinking outside the box has its advantages :)
 
My company doesn't believe in fuel conservation. We've been told to NEVER single engine taxi. If we run out of fuel on the taxiway, we should come back. The reason for this is "we don't pay for the fuel".

No, I'm not joking, management actually said that. And no, when prompted, they really won't change their viewpoint. They are also shocked we lose RFP after RFP...think there's a connection?

That being said, 290 knots in the climb is what bombardier recommends. I use pitch mode, 2.5 nose up, and let 'er rip. That generally gets the job done up to about FL300 or so. Once you get passed the 290/.70 crossover it starts to climb a little better, it's around FL250-FL260 that is gets "stuck". Sometimes you really just have to stop your climb and step climb it up on the long legs.
 
If I know that I am not going to be step climbing I peg 1000fpm out of 10K and hold that. The speed normally builds to around 320 and then starts coming back down. Even at ISA+15 or so that will get me into the upper 20s. After that (and I generally don't go above F320 in the summer unless we are going a LONG ways) it is either speed mode (which tends to oscillated all over the place) or 500 to 800 fpm until I get where I am going or the mach number gets down to the low .6X.

I saw ISA+19 at FL200 the other day.
 
We're on the 290 kts plan, too. So, I'll bug 290 crossing through 10K and hold that for as long as I can in VS speed mode. I'll generally be down to 500 fpm by about FL250-260. By the time I would need to dial it down lower than 500 fpm, we've hit the mach transition, and we're doing .70 in the climb, which is a lot easier. I haven't had to slow it below 500 fpm except for once so far, and that was going up to FL310 on an ISA +15 day. Just make sure you keep adjusting the thrust levers as you climb, too. I've seen CAs forget to do that and wonder out loud why the thing was climbing like more of a pig than usual.

Found out the other day that the FMS will actually say "unable cruise altitude" if it can't hold the programmed cruise speed with the N1s on the cruise carats.
 
Blackhawk said:
I am concerned that this was not taught to you in ground school, or that a captain has not taught you this. The reason for the 250/.70 (I thought it was 180/.70, but it has been a while), is not just fuel conservation, but for thrust for the engines. Turbo fan engines need airflow to develop power; if you get below the cruise climb airspeeds you really are not gaining anything- the short term gain is more than offset by the thrust you loose as airflow into the engines decreases.
Also, if you are using these airspeeds but not getting a climb rate, you need to stop you climb. You are probably getting into the coffin corner. Continuing to climb will lead to this:
http://ntsb.gov/ntsb/brief.asp?ev_id=20041015X01633&key=1
Click to expand...

I appreciate the concern. I did learn about high altitude aerodynamics back in the student days and my airline does teach it during groundschool as well. When I said "hanging by the engines", I didn't mean hanging on the verge of a stall. I meant simply a slow acceleration from .70 to .74 (around FL330) because you're left at a high deck angle, which is what you were touching on.

Speaking of a high deck angle, a captain I was flying with showed me a trick to help the CR2 speed back up at cruise. Once you've captured the altitude, hit the pitch mode and put the nose down a bit. You'll lose maybe 20-30 feet but it'll reduce the deck angle and get the airplane accelerating faster.
 
I modified the profile a bit. I start the climb at 250 above 10K and then peg the VS between 700-1000 ft/min at FL200 depending on how heavy we are.

I flew with a captain that used to work at Indy Air and he said they would start the climb above 10K at 320 KIAS and that would work well.
 
Another reason 320 works well (so I've heard, I've never really tried it) is speed mode will hold it better than 290 or 250.
 
BobDDuck said:
If I know that I am not going to be step climbing I peg 1000fpm out of 10K and hold that. The speed normally builds to around 320 and then starts coming back down. Even at ISA+15 or so that will get me into the upper 20s. After that (and I generally don't go above F320 in the summer unless we are going a LONG ways) it is either speed mode (which tends to oscillated all over the place) or 500 to 800 fpm until I get where I am going or the mach number gets down to the low .6X.

I saw ISA+19 at FL200 the other day.
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:yeahthat:

Once passing 10K set the V at 1000fpm and let it accelerate. It will climb into the 20K's at around 290 then set it at 500fpm. The CRJ-200 needs momentum to climb. It does not like slow. We were fully loaded to 53K and we got it up to FL330. It was a struggle but we were not hanging on the engines once we got up to altitude.
 
See, we all know how to operate our birds effectively and safely. However, those SOP Nazis will say, 'conserve fuel' until they are blue in the face. Grrr... :banghead:

Any by 'SOP Nazis' I mean managment types who say the ARE line qualified, when in fact they haven't touched the line in about 2 years. Hmm...who could I be referring too? :rolleyes:

This takes me to another rant....APU usage. Nowadays we are told to only use the APU (on the ground) when extreme environmental conditions exist. Hmm...so when it is 80 degrees with high humidity it might not quite fit the term 'extreme environmental conditions' however it IS going to be hot in the back. This soon-to-be-captain is gonna do what it takes to keep the passengers happy and return to fly on us. I am all about saving fuel and keeping the company moving - but not at the expense of losing customers :banghead:
 
Been using 250 till 10'000,
The the climb profile using the PPAS (Pilot Performance Advisory System) cards. They are similar to VSpeed cards-only they show a table of what the optimum fuel savings climbing speed will be accounting for the weight and winds. Also on this card is a Min. Safe speed.
Our Limitations section in the standards manual also note that in climb we must fly at SAFE + 10 , and at all times respecting +300 FPM climb. If that can't be maintained=your done climbing-request a different altitude.

Also there are reference charts to use when looking at what altitude is possible given weight and the ISA deviation.
 
I don't like how management is pushing us to accept a sub 500fpm climb in the last few hundred feet. It crawls up there. Step climbing is much better IMO.
 
wheelsup said:
My company doesn't believe in fuel conservation. We've been told to NEVER single engine taxi. If we run out of fuel on the taxiway, we should come back. The reason for this is "we don't pay for the fuel".
Click to expand...

Geez...Why would you never want to SE taxi? What negatives does it have to warrant the company specifically saying not to do it?

At my company I believe we pay part of the fuel bill, so they encourage SE taxi both for Take-Off and after landing. Plus I find when we're not heavy and especially after landing that with both engines running it's necessary to get on the brakes, slow down.....speed up, brake and repeat...On a SE the speed is more manageable.

Additionally...especially at Newark, to have both engines up and the APU for an hour long taxi would be about 900lbs of fuel...For a short taxi it's obviously less but still adds up.
 
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