Flex Jet CL-30 Questions

[Bladestall]

I am flying the 300, Part 91 and have heard rumors that Flex Jet is doing some stuff that we are considering already.

1. Are you guys doing FLEX Take offs?

2. Do you have a fault reset guide for your pilots?

3. Did you really have engine problems from transferring the bleeds to the engines and killing the APU prior to Take Off?

4. What have you heard about 45,000 lbs MTOW?

 

[ultrarunner]

How would a FLEX takeoff be conducted on a FADEC airplane??? That doesn't sound right.

 

[WhatsUpNow?]

How would a FLEX takeoff be conducted on a FADEC airplane??? That doesn't sound right.

We do it all the time in the CRJ-700, which is a FADEC airplane.

 

[ultrarunner]

We do it all the time in the CRJ-700, which is a FADEC airplane.

So how is it done? You guys have a FLEX detent? Or do you just set a target N1 or EPR like on non-FADEC engines? You obviously have a chart for this.

 

[XTW]

Adjust the T/O "assumed" temperature maybe?

 

[ultrarunner]

Adjust the T/O "assumed" temperature maybe?

Yeah, I suppose that would work if you have direct access to send that info directly to the FADEC.

 

[Bladestall]

Of course you do! Just look at the Airport Anal and look at the highest assumed temp available for takeoff weight. Enter that assumed temp under PERF/TAKEOFF/OAT in the FMS. As a result V speeds and N1 Target are adjusted. T/O detent now becomes a FLEX setting.

Another method would be to enter an assumed temp that creates a balanced field legnth in the same section of the FMS, baring anyother limitations such as climb, brake, obstacle the N1 and Vspeeds would be adjust for the FLEX Takeoff.

Bottom line Balanced Field Length is alway met. The CL-30 is such a high performance aircraft at intial climb (7-9 fpm at MTOW) that a Max Blast T.O. is complete over kill in all situations.

 

[ultrarunner]

Ahhh, that's pretty slick. The FADEC airplane I fly does not quite work that way. We can enter AT in the FMC and naturally it'll spit out the appropriate V speeds and N1, however our FADEC takes temp directly from the ADC's of which we have no control over. As a result, the N1 bugs will allways show 'power for the day'.

 

[ProFracPilot]

...that a Max Blast T.O. is complete over kill in all situations.

Perhaps you meant to say "...in almost all situations".

You're likely required to perform a rated power takeoff with a wet runway and /or every 100 hours, or some such limit. But even with that, you'll do them much more often.

I don't care what the perf data / computers tell me I can do for runway and 2nd segment on a given day. If I'm departing from mountainous terrain, I want "a max blast T.O." (to use your term) to get up and out of there. There are aircraft that will provide you perf data to flex, say, out of ASE. I won't do it. In this scenario I'm going to use rated takeoff power for 5 min or until clear of terrain, whichever occurs first.

Flex takeoff certainly reduces maintenance costs over time on the engines. But it is made available only as a convenience.

 

[Bladestall]

Absolutely! I ment to say in alot of situations. Thank you for the correction.

Your right.

 

[frac pilot]

I am flying the 300, Part 91 and have heard rumors that Flex Jet is doing some stuff that we are considering already.

1. Are you guys doing FLEX Take offs? No, TO detent and go. The FADEC figures it out for you.

2. Do you have a fault reset guide for your pilots? No, you learn them as you go and through Field Service Reps.

3. Did you really have engine problems from transferring the bleeds to the engines and killing the APU prior to Take Off? Haven't heard of that til just recently.

4. What have you heard about 45,000 lbs MTOW? Nothing.

 

[GCAP]

Lots of bad answers here. Some acft use a TRP ( thrust rating panel ) to select "assumed temp" others use data entry on the FMS. You are not doing yourself any good using full rated thrust when it is not necessary. Rumor used to be that there had never been a failure on a JT8 when flex was used.
When using flex, full rated thrust is still available when needed.

 

[FraxJockey]

Allow me to chime in here.

First of all, the FMS inputs in our planes are for TAKEOFF/APPROACH data calculations. There is no way that I am aware of to select an assumed temp. for FLEX takeoffs. The fact our takeoff N1's rarely exceed 93% anyway is a testament to how derated these engines are. There are NO TBO's, just inspect and go. Therefore, I believe any gain would purely be in fuel if there IS a way to flex the TO. Flex takeoffs (or reduced power TO's on the older Boeings) if I remember correctly serve to extend the service intervals on the engines, since there are no TBO's then there is no point in doing so. The engine has the capability to produce 7000 lbs of thrust (flat rated at 6826 on the CL300) and has room to expand to 9000 lbs.

Fault reset guide...sure CTRL+ALT+DEL, in other words power down. If that doesn't work, disconnect the BATTS after you power down. This clears up most erroneous CAS messages.

I haven;t heard of any engine problems with reference to the bleeds.

The current limit is 39000 Ramp & 38,850 MGTOW. I havent heard of any proposed changes. Even if you took one of our typical CL300's and filled it to MZFW and then added max fuel you would only be getting 41250 (27,100 MZFW + 14150lbs. fuel). I think 45000 lbs. is overkill.