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

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

I don't really use flaps 8 for T/O too often. We are normally heavy and doing flex takeoffs so flaps 8 speeds are really fast, plus if its gusty or windy you are having to fight it on the ground for longer while going faster. I prefer to just get up and go so its flaps 20. Now coming out of DEN or HLN flaps 8 makes sense for obstacle DP's. Its all personal pref. If the winds are calm and we are light flaps 8 is fine, otherwise I normally just use 20- especially since its what I am accustomed to in the other planes.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Soul Brotha' said:
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).
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I will agree with you that it is a technique and as long as you are within the SOPs then you are "legal" to operate a certain way...but it can also be sloppy and a poor ride for those in the back (you know, the ones paying the bills).

Here are some of my observations, although my plane isn't an RJ, some still apply.

In icing conditions, a high deck angle enables the plane to build ice under the leading edge and aft of the heated areas. Adding the flaps allows the ice to impact the heated surfaces where it belongs.

The AOA will show you efficiency of lift, it is probably a negligible difference between an inefficient deck angle and having a notch of flaps. Besides, you are only operating this way for a few minutes; you aren't saving more than a few quarts of fuel. High deck angles aren't as comfortable for passengers, and requires more thrust to hold the pitch.

As you are decelerating in the terminal area, using the flaps to slow you down eliminates extra throttle movements and makes you less of a throttle jockey. If you throttle back to 170 kts, when you add the flaps you power back up....repeat. If you add the flaps in the decent, the power is set once.

Yes…most old timers see the speed brakes as an “error correction” device.

There is a difference in flying the plane, and flying the plane well.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

A few things to note about some of the responses on here...

Reference your speed card: Vref+10 for the flaps setting and weight gives you your manuevering speed. Use it. I seem to remember that 183 knots was the slowest clean manuevering speed you had for 47,000 pounds.

If the final is long and youre slowed to 190 or so, keep the plane clean and idle down... you'll burn much less gas that you may need later. If you are a bit lighter, you'll be able to do 180 clean. There is no reason to burn gas unless you have to (re: icing conditions where you have to have the engines spooled to keep the wings warm). Also, waiting until 190 knots or less to put in Flaps 8 and/or 20 will negate that annoying pitching motion. I also took the autopilot from VS or DES mode to PITCH mode if we had to select the flaps at a higher speed. That has the same effect.


I never used flaps or speed brakes unless they were necessary... I could typically beat projected burn for a flight by several hundred or a thousand pounds by using these techniques. Approach controllers expect 1000-1500 feet per minute unless otherwise requested. Idle at clean manuevering will give you around 900-1000.



In a slam dunk situation, 210 knots (that was our max flaps 8 and 20 speed at 9E), flaps 20, and full speed brakes will take you from a 12,000 foot downwind like a brick. Make a smooth transition and the passengers will barely notice.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

PeanuckleCRJ said:
In a slam dunk situation, 210 knots (that was our max flaps 8 and 20 speed at 9E), flaps 20, and full speed brakes will take you from a 12,000 foot downwind like a brick. Make a smooth transition and the passengers will barely notice.
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I've been "told" that fully configured and full spoilers will take you down about 4000 fpm at REF45+5 very nicely. Works well when you ummm... mistake which airport you are landing at and have to get down in a hurry.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

PeanuckleCRJ said:
In a slam dunk situation, 210 knots (that was our max flaps 8 and 20 speed at 9E), flaps 20, and full speed brakes will take you from a 12,000 foot downwind like a brick. Make a smooth transition and the passengers will barely notice.
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You could also try lowering the gear instead of using the boards.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

It's all about technique, really. Whatever works for you that keeps it within limits and SOP. I don't consider the spoliers a "mistake lever." It's installed in the aircraft, so they're there for me to use. Now, some idiot that likes to write manuals that never flies the line has put in our new FOM that we can't make any descents below 10K at 2000fpm. Denny will tell ya, that makes DTW a bit of a challenge sometimes. Even the check airmen where blind sided by this one. From what we've HEARD it's going away soon. When (not if) ATC in DTW decides to slam dunk you, you're the moron asking for delaying vectors b/c you can't get down in time. Makes places like PNS, DSM and MSN darn close to impossible to fly into since they almost ALWAYS dunk you into there.

One flaps 8/20, I prefer flaps 20. I had a "discussion" with a CA on this one last week. His reasoning was "While you're fighting to keep the plane in the air at flaps 20, I'm stopping on the ground." My response was "Uh, there's no fighting. This thing will fly on one engine. And while I'm climbing out via the profile, you're trying not to blow a tire." I guess I've always been told (from multiple sources) that high speed aborts tend to result in less then desirable outcomes sometimes. He responded by slamming on the brakes when we landed to show me how quickly it stops. He was a little lost when I started talking about increasing energy on a takeoff as opposed to decreasing energy when you're landing, ie you have to take your momentum and flip it the other way QUICKLY on takeoff. On landing, your speed has been steadily decreasing for a bit already. Obviously, in high elevations, flaps 8 is the way to go. Anything else, and I'm partial to flaps 20.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Flaps 8 = better (less power) flex off the longer runways = less ITT = more reliable and stronger engines = saves company $$ by increasing the inspection cycle.

I'm pro-flaps 8 :). I'm actually pro-max flex, but normally that's flappers 8. I'm also partial to the reduced pitch changes on t/o that flaps 8 gives.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Today out of MSP, we could flex flaps 20, but not flaps 8. Doesn't always mean you're gonna be able to flex.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

What runway? Normally flaps 8 is better for the longer runways (say 8000'+), which we generally operate off of. The ACARS tells us which is the best flex, 4/5 its Flaps 8.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

21L AND 17 in MSP.

I'm normally all about the flexing, too. However, full thrust has its advantages in MSP right now. They're tossing guys off intersecting runways with landing traffic about 3 miles out. Today, they cleared us to takeoff as soon as the guy landing passed the intersection of the runways. There was another guy on a 5 mile final, and two more guys BEHIND us got launched before he landed. It's crazy here with the runway closure.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Blackhawk said:
Why not just use the boards??? They were put there for a reason.
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If you need to get slow and down fast, gear is a good option. Like, say, if ATC leaves you out to dry and clears you for the approach 10 miles out at 9000 ft.

Now, if you're not gonna be landing in the immediate (like next two minutes) future, I'd go with the boards.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

wheelsup said:
Flaps 8 = better (less power) flex off the longer runways = less ITT = more reliable and stronger engines = saves company $$ by increasing the inspection cycle.
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Also, flaps 8 takeoffs increase initial climb rate, reducing the fuel burn = more money saved. The cheapest way to operate the airplane is with max flex and lowest possible flap setting. That's exactly why WorldFlight (NWA's computer performance/flight planning system) generates takeoff data in a specific order. It will always try to give you the highest possible flex temp for your given weight along with the lowest flap setting, and prefers a rolling takeoff instead of a static takeoff. There's no reason to try to out-think the system. It works just fine, and it has large margins of error built in.

I'm pro-flaps 8 :). I'm actually pro-max flex, but normally that's flappers 8. I'm also partial to the reduced pitch changes on t/o that flaps 8 gives.
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I'm with you 100%.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

Delta does the same thing... We nearly always use flaps 5 for our 757 and 767 takeoffs unless flaps 15 is required. It's not uncommon to see a Flex 57 or even higher assumed temp takeoff.



I heard about the 2000 fpm rule... Somehow I wouldn't doubt that Matheny was involved with that one. I can understand no more than 2000 fpm below say...3000 agl... but, come on!
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

For educational purposes, what is "flex?"
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

A FLEX t/o is using less than full power. They are all about doing FLEX t/o's at AWAC. Saves wear and tear on the engines.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

As temp rises the N1 speed of the engine comes down for a set power setting due to lack of performace. So basically you find the highest temperature that you can safely take off at and find out what the N1 speed will be. Then you use a power setting that will generate that N1 speed for take off.

For example, if it's 25 degrees C out normal "max power" might generate an N1 of 95.5%. You (or the computer) then looks at the performance data and see that the highest the temp can be and you still get off the runway is 47 degrees. "Max Power" at 47 degrees might generate an N1 speed of 84.5%. So then you take off using a power setting less then "max power" that will give you 84.5% N1.
 
Re: CRJ-200 - spoilers or flaps for speed restricted descent

PeanuckleCRJ said:
Delta does the same thing... We nearly always use flaps 5 for our 757 and 767 takeoffs unless flaps 15 is required. It's not uncommon to see a Flex 57 or even higher assumed temp takeoff.
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We do the same at da Tranny. ACARS retrieves the performance info from the Aerodata system and it tries to give the lowest power setting (usually a flat de-rate rather than a flex) with the lowest flap setting. Usually that gives you a 12% de-rate with flaps 5. Saves a ton of money on engine maintenance. The guys on the 737 can even flex further after a de-rate.
 
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