Regional a/c flight profiles

[BoilerUP]

I'm doing some reseach for a project on "regional" aircraft, and I can't really find the info I am looking for from the manufacturers. All I've been able to find is a generic chart in Aviation Week with no supportive documentation over a 200nm segment. What I'm trying to find is the operational and economic break-even stage length of RJs vs. modern turboprops.

I was hoping to get climb/cruise/descent speeds and fuel flows for the following aircraft:

E145
E170
CRJ2
CRJ7
Q400
ATR7

Thanks for the help!

 

[Paul R. Smith]

A cool subject...

The climb profiles are usually one of two depending on the aircraft your in. The crz profile is usually a trade off between schedule and fuel and depending on which is more important at the time. The dispatcher will give you a profile that is more fuel conservative depending on how much the slower speed will impact the schedule.. so you can be dispatched sched/fuel or fuel/sched, or in som very rare cases you can be dispatched Long range crz which is obviously a fuel first lets get there second deal. But I don't think That happens very often..I have never seen it in five years of flying here...except for your alternate fuel planning.

This is very hot topic right now. Climb and descent profiles are becoming increasingly important at ny company due to the volume of aircraft in and out of our hubs...So here standardization is the key to maximizing the airport's volume capability. I.E. one guy climbing at 200 kias with 2500-3000fpm while a guy behind him at 310 kias & 1000 fpm can cause problems as you can imagine especially if they are both the same company operating the same aircraft..ATC expects you to fly about the same since you are comin from the same background ya know.
The same goes for descents...When ATC issues you a descent with P.D. and maintain max forward speed...that does not mean descend to an altitude where you can achieve 320 kts(VMOredline in our case)It means stay high with a higher TAS and descend at the last minute to achieve your crossing resrtiction if applicable. However Not all controllers understand this so they contribute to the problem as much as we do in our non-standard operations. They will issue a max forward speed to a much lower aircraft and give a 270 kts restriction to a higher aircraft and wonder why the higher aircraft is catching up with the lower traffic causing compression at arrival fixes. ATC is not a bunch of PHDs they are only maybe a slightly smarter bunch than we are. And thats not saying alot . Your best bet is to follow your own profiles as colsely as you can. And ATC can make that difficult especially in and out of NY airspace where they seem to get you down fairly early so you can burn more gas....
Basically it is not a reccomended procedure to launch and ERJ ( a very capable aircraft IMO) out of ORD on a NE heading and climbing at 180 kts and 3500 fpm just because you on course heading is southwest...It might save gas but your giving the controller a real headache not to mention people behind you. I realize this stuff may not help that much but Its all I can muster out of my shi#ty typing ability for now.

I would give you our exact profiles but just in case we do it better than someone else I don't want to give the competition any ideas. Sorry man.

And a caveat: Someone will come along in about 1-5 posts from now and say that I'm "full of **CENSORED****CENSORED****CENSORED****CENSORED** and that this is the way your really supposed to do it..etc" and thats just how it is...I don't know why I bothered.

Your best bet is to pm some guys who you know operate the equipment your talking about and ask them directly. But seriously some of this stuff is trade secrets at least to me it is but I'm a paranoid fella.

 

[~~~^~~~]

Look on Bombardier's, ATR's and Embraer's web site for some excellent charts on turboprop efficiency.

The speeds of these airplanes are effected so much by IAS / TAS that I am not sure how you are going to correlate your data. Generally you can convert IAS to TAS by multiplying IAS by ( 1 + (FL * .02 ))

For example the profile of the CRJ200 at my operator is:

Airspace restricted to 10,000 feet ( 200 / 250 / 290 ) depending on which airport you depart. Usually 250 KIAS to 10,000 feet. Figure 3,600 per hour burn climbing at 2 to 4,000 FPM

Accelerate to 290 KIAS and hold that to cruise altitude. Climb rates drop off to 1,500FPM all the way down to the ATC required 500FPM. 290KIAS at FL300 is 464 True airspeed, ( 290*1.6 which is about 9 knots faster than reality, but close enough ) at 2,800 to 3,000 pounds per hour. This is our cruise speed and we prety much cruise within a couple percentage points of our climb power setting. The CRJ200 seems to always be around 450 to 455 knots true airspeed.

Decent - within 10 knots of limitations ( 330 to 335 KIAS ) 480 KTAS to 10,000 feet, then as restricted by airspace. Fuel burns probably drop to something less than 1,200 pounds per hour.

Of course there are a bunch of other considerations. How long do the engines last? The DO328J's were going through engines with less than 2,000 hours on them, while some ATR operators have gotten 15,000 hours between engine removals. Also, the jets' speed means you can get more flight legs out of your airplanes every day. With ASA it is thought that the Dash 8 Q 400 was simply too big for the congested ramp space at the Atlanta airport and with any airplane you have to consider the costs of an additional training department, spares and mechanics.

If you get all of this worked out, let us know. If you want to cheat, you can buy the data from Conklin and DeDekker.

Regards,
~~~^~~~

 

[Biatch5]

Someone will come along in about 1-5 posts from now and say that I'm "full of **CENSORED****CENSORED****CENSORED****CENSORED** and that this is the way your really supposed to do it..etc" and thats just how it is...I don't know why I bothered




Paul R. Smith is full of sh!t

 

[BoilerUP]

PRS

I know the topic is a bit (well, extremely) dry, but I certainly appreciate your input. Its a perspective I hadn't really considered.

Last fall I heard a NY Center controller tell one of your company planes climbing out of EWR she needed at least 300kts in the climb. There was an AIRMET as well as reports of severe turbulence in the area, so the crew responded they could not go that fast. The controller told them to go as fast as they possibly could, given the conditions. Seemed a bit odd to me at the time, but I don't operate out of NY very often so I'm not aware of their procedures.


Fins

Thanks for the info. I'm certainly not an accounting expert, so I won't quite be breaking it down into fractions of cents. I suppose what I'm really interested in is the effectiveness of the Q400 vs. a 50 and 70 seat RJ. I know CVG-IND (for example) the Dash would be much more efficient, but I'm curious about how far out those benefits go (BNA, STL, etc).

 

[~~~^~~~]

Boiler:

The Dash 8 Q400 is an awesome machine. Have you looked at the Bombardier site. They do an excellent job at making the case for that airplane.

The same applies to the ATR, even more so. The ATR is not as fast, but 66 people doing 300 MPH on 200 Gallons per hour is impossible to beat.

 

[jobear]

Dry!!! I fell asleep 3 times before i could post this useless drivel


Jo-sleepy-bear

 

[Paul R. Smith]

Someone will come along in about 1-5 posts from now and say that I'm "full of **CENSORED****CENSORED****CENSORED****CENSORED** and that this is the way your really supposed to do it..etc" and thats just how it is...I don't know why I bothered




Paul R. Smith is full of sh!t

Thanks Biatch!..I was beginning to wonder.