CRJ-200 - spoilers or flaps for speed restricted descent?

C150J

Well-Known Member
This question revolves around aerodynamic efficiency and fuel burn.

Scenario: you're being slowed to 180 for an approach WAY out (ala CLT) at 8,000 feet. They clear you to 4,000 at 180 knots. You know that once you hit 4,000, you're going to STAY there a while before initiating the approach.

I don't have much time in the airplane, but I just used flaps 8 and spoilers for the descent and maintained 180 fine level with that setting (duh, I know). I think that this would be more efficient than throwing flaps 20 at 8,000, but I could always be wrong.

Any insight for the guys that are CLT based? I have only been in there three times in the past year.

Thanks!
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

What's ref for flaps 8 at a 46 or 47 card? I don't think you can do spoilers @ 180 at those weights.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Most of our planes don't even HAVE flaps 8. If I'm gonna be below about 210 kts, it's flaps for me. If I'm in a plane with flaps 8, then I'll stay 8 degrees until I'm slowed under 200, then I'll go 20.

Wheels is right. Make sure you check your ref speeds before using spoilers or turns.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Flap extension speeds for awac are:

Flaps 8: 180
Flaps 20: 170

They can be done above that, but those are the recommended speeds. In fact, the Company doesn't want flaps coming out at all above 200, even though 215 is the "hard" limitation here. Yes, they are really, really, conservative.

J, if you're really far away from the airport Flaps 8 descents aren't a big deal. I think the reason you find people throwing flaps 20 out is to aid in increasing the descent rate. In your example, if you're "way" out from the airport no biggie, flaps 8 @ 180, and do a nice descent in speed mode. If you're not gonna hit the fix @ 4000' (can't remember which one) I'll throw flaps 20 out. It gets the nose down further anyway, that was a big thing for my OE instructor.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Bombardier's limitation for flaps 8/20 is 230 kias. SKW's limitations are 215 kias.

Pinnacle's CRJs don't have flaps 8? Why?
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Flap extension speeds for awac are:

Flaps 8: 180
Flaps 20: 170

They can be done above that, but those are the recommended speeds. In fact, the Company doesn't want flaps coming out at all above 200, even though 215 is the "hard" limitation here. Yes, they are really, really, conservative.

J, if you're really far away from the airport Flaps 8 descents aren't a big deal. I think the reason you find people throwing flaps 20 out is to aid in increasing the descent rate. In your example, if you're "way" out from the airport no biggie, flaps 8 @ 180, and do a nice descent in speed mode. If you're not gonna hit the fix @ 4000' (can't remember which one) I'll throw flaps 20 out. It gets the nose down further anyway, that was a big thing for my OE instructor.

Thanks! We were empty too, allowing for the Vref approach/maneuvering + 17 knots deal. Just never thought of that while asking the question.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

You guys are restricted to 215 on the flaps? We are restricted to 220, but the red line doesn't start until 230 and even then there is a 3-7 knot buffer before the clacker goes off (or so I've been told).

Mostly, if I know I'll be leveling out at a lower altitude and holding the speed for awhile I'll try to get away with as little flaps as I can. While I'm not really a fan of the spoilers, it is cheaper to use them to get down and slow down if you are going to be leveling off later. Of course, that doesn't always work. We use a Vref+10 off the card for the flap setting. So if at 45K the Vref for flaps 0 is 164 (making this up) we are good to slow down to 174 before throwing out flaps 8.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

I am not sure about the percentage of PNCL's fleet that is flaps 8 but I know that not all of them are by a long shot. If I had to guess I would say its about 50/50 on flaps 8/20. We use the flap 8 planes alot out of msp to the higher elevation fields but they are in all the bases. What I have always been told as to a reason is of course= PRICE. Maybe Kell has more info but PNCL has always been good at keeping costs down... even though NWA bought the planes... o wait they have the oldest fleet in the industry... don't get me started on Red Tail...:banghead:
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

O- and back to the original question... I love flaps 8 planes cause from 215 to 170ish (depending on weight) you can use flaps 8 and its not a huge change as opposed to 0-20. Anything below 200 will have flaps for sure (my technique) and anything below 170 is flaps 20 without looking. Otherwise its ref +10 as a min. Keep in mind you can pull the flaps back up if you are slowed to 190 waaayyy out and then they ask for 230... bring the flaps up and add about 5% on the N1s and you are good.. technique always prevails after the company/aircraft lims. You will have plenty of time to figure it out and no one way always works the best. Are you going to be pulling spoilers when you are ref+20 and mod turbulence? or just go from flaps 8 to 20.... "flaps 20 plz".
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

You guys are restricted to 215 on the flaps? We are restricted to 220, but the red line doesn't start until 230 and even then there is a 3-7 knot buffer before the clacker goes off (or so I've been told).

Mostly, if I know I'll be leveling out at a lower altitude and holding the speed for awhile I'll try to get away with as little flaps as I can. While I'm not really a fan of the spoilers, it is cheaper to use them to get down and slow down if you are going to be leveling off later. Of course, that doesn't always work. We use a Vref+10 off the card for the flap setting. So if at 45K the Vref for flaps 0 is 164 (making this up) we are good to slow down to 174 before throwing out flaps 8.

Add 10 knots to that.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Duh... I've got to dump all the numbers from the ATP written I've still got stored and put back in the useful stuff.

230
230
185
170

Ok. I feel better now.


Thanks Mr. Training Department Captain!
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

I think people are scared of me now that I came over to the darkside.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Ken, it gets even more confusing. NWA owns the planes, but PINNACLE paid for the flaps 8 conversions.

"We're gonna start flying into Helena, MT! Isn't that great?"
"Uh, all of our plane are Flaps 20."
'Yeah, so?"
"Um....might wanna do some research there, genius."

So, we had to pay to retrofit some CRJs with flaps 8 so we could legally do Helena. NWA WANTED to take those planes and move them to XJ, but we told them we wanted the $$$ we put into them for the flaps 8. So, from what I hear, different planes have been earmarked for XJ. They were SUPPOSED to start going over there this month. Not sure if that's happened yet.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Ken, it gets even more confusing. NWA owns the planes, but PINNACLE paid for the flaps 8 conversions.

"We're gonna start flying into Helena, MT! Isn't that great?"
"Uh, all of our plane are Flaps 20."
'Yeah, so?"
"Um....might wanna do some research there, genius."

So, we had to pay to retrofit some CRJs with flaps 8 so we could legally do Helena. NWA WANTED to take those planes and move them to XJ, but we told them we wanted the $$$ we put into them for the flaps 8. So, from what I hear, different planes have been earmarked for XJ. They were SUPPOSED to start going over there this month. Not sure if that's happened yet.

As crazy as that is I wouldn't doubt that the convo went along those lines. From listening to the call last night evidently XJ is still getting the 15 -200's but they are "delayed" as far as deliveries because they can't staff them. I wish they would just take them at this point and I could get a couple more days off a month. Plus, with DL -900 deliveries just a couple months away I forecast a replay of last winter if we don't lose the 15 to XJ. As usual we will just need to wait and see I guess.:panic:
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

I don't have much time in the airplane, but I just used flaps 8 and spoilers for the descent and maintained 180 fine level with that setting (duh, I know). I think that this would be more efficient than throwing flaps 20 at 8,000, but I could always be wrong.

You're doing it right, and I'm impressed that you're thinking about that stuff with low time in the plane. I wish most of my FOs would have been thinking like that.

Throwing out flaps before they're needed is just bad technique, and horribly inefficient. When I had FOs call for flaps 20 simply because we were slowing below 200 knots, my response was simply "how 'bout we wait until we need them." Flaps 20 drastically increases your fuel burn to maintain a given speed in the CRJ. If you've got your spoilers out, then use vref+17 to determine when you need flaps. If your spoilers are stowed, then vref+10. Only exception is when it's getting turbulent and you need a few knots extra for a buffer.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

As crazy as that is I wouldn't doubt that the convo went along those lines. From listening to the call last night evidently XJ is still getting the 15 -200's but they are "delayed" as far as deliveries because they can't staff them. I wish they would just take them at this point and I could get a couple more days off a month. Plus, with DL -900 deliveries just a couple months away I forecast a replay of last winter if we don't lose the 15 to XJ. As usual we will just need to wait and see I guess.:panic:

Figured something like that was happening. Talked to a dispatcher that said they were still on the books. What else did they say last night? I was fighting with a fussy 2 year old about then.

You're right about the staffing issues once we start getting the Delta planes. It's gonna get REAL interesting if we've still got those 15. I think they can only take like 2 a month, so we're at least gonna have 9 of 'em in Jan.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

ef!! i just realized how much i have forgotten about my plane since i have been away. I dont even remember the flap speeds. is it 215 for flaps 20/8?? Boy, am I gonna have A LOT to study when i get back!
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Another question for you CRJ drivers, do you prefer flaps 20 for T/O vs. flaps 8? I've had a few Captains that prefer flaps 20, and others that like flaps 8 due to various reasons. Just curious what others think.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Another question for you CRJ drivers, do you prefer flaps 20 for T/O vs. flaps 8? I've had a few Captains that prefer flaps 20, and others that like flaps 8 due to various reasons. Just curious what others think.

With flaps 20 you will have a shorter T/O roll, but your initial climb performance will suffer. I don't have a preference, but it's sure nice to have that climb performance.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

You're doing it right, and I'm impressed that you're thinking about that stuff with low time in the plane. I wish most of my FOs would have been thinking like that.

Throwing out flaps before they're needed is just bad technique, and horribly inefficient. When I had FOs call for flaps 20 simply because we were slowing below 200 knots, my response was simply "how 'bout we wait until we need them." Flaps 20 drastically increases your fuel burn to maintain a given speed in the CRJ. If you've got your spoilers out, then use vref+17 to determine when you need flaps. If your spoilers are stowed, then vref+10. Only exception is when it's getting turbulent and you need a few knots extra for a buffer.


I think it comes down to technique/time in frame/etc. You fly with guys who use Flaps 20 because they don't like the nose up pitch the -200 gets when it get's below 200KIAS. I know of guys who don't use the spoilers. To them it is a mistake stick(which I think is one of the dumbest things ever). Then there are guys who use vref+15 when you need the flaps with spoilers out. As long as you are safe and flying within your company's SOP it's all good baby!
 
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