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Reduced thrust takeoffs

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Big Picture

Member
Joined
Oct 1, 2005
Posts
20
Just wondering if any corporate operators do reduced thrust takeoffs. It was pretty common in my old job (pt. 121) but I haven't seen it used since I went corporate.

We have a Falcon 50 on MSP Gold and I couldn't tell from the Honeywell website if there would be any financial incentive for an operator to do reduced thrust t/o's.

Any comments?
 
It's been a while since I have looked, but I think Dassault provides flex power settings. I believe it's for noice abatement, and now that I think about it, the thrust cut-back is after TO, I think.

It's not a common issue on corp planes though. Everyone is on an engine maint. program, and no corp operators are flying 5000 hrs a year on their engines, like the airlines, so longevity is not a critical issue.
 
Big Picture said:
Just wondering if any corporate operators do reduced thrust takeoffs. It was pretty common in my old job (pt. 121) but I haven't seen it used since I went corporate.

We have a Falcon 50 on MSP Gold and I couldn't tell from the Honeywell website if there would be any financial incentive for an operator to do reduced thrust t/o's.

Any comments?
We occasionally do them in our G-V, it is called a "Flex Takeoff"... We can do them in the Falcons, but never do...
 
We do it all the time (wx permitted). In fact the new R/R power by the hour for the BR710's requires it.
 
I utilize Flex EPR at times, then after T/O its comes back to Climb EPR! Depending on weight and weather, then I use Min EPR!!
 
There was a big discussion about 3 weeks ago on this issue on the NBAA airmail. It was centered mostly on the newer Gulfstreams. From what was said, most of those guys do use a "flex" setting. They said they used that setting more as a comfort for the pax. All of them said full power really puts the folks on board firmly into their seat, almost at a level that is uncomfortable. It sounded impressive.

If the engines are on a MX program, I don't know why anyone would use a reduced power setting, unless it is noise. Let the JSSI/MSP folks worry about it. LIke 1 guy said, you got it, so use it. The engine MX program folks get a check every month for the operators, so by doing reduced power take offs, you are not doing anyone a favor but them. You have to pay them the same amount based on hours, not take off settings. The Gulfstreams are the exceptions.

Also, not all aircraft are approved for reduced power take offs. If it is not in the AFM, I would not be doing them. Some guys get their #s, then go over to 40C and see what N1 they can use with the available runway, then use that power setting. That is not approved and the V speeds will not be accurate. Just imagine the rug dance you'll be doing while telling the FAA of your unapproved reduced power take off procedure as your ticket is getting shredded. It's really now worth it. Don't step on $20s to pick up dimes.

Finally, remember, the N1s in the tab data are Minimun power settings, not the max. That is the lowest N1 that you must have in order to achieve the desired performance for the specified conditions you are computing. At the end of the day, it's the Temps that will get you, not 96% N1 when it's supposed to be 94%, but overtemp that bad boy, and you are creating problems that may or may not destroy the engine. Also, modern engines are going to have tattle tales on them, so be aware of that as well.

If you have DEECs, push it to the stops. FADEC, 3 clicks and hang on. EECs, set the power to get at least the # you have looked at in the book. The performance data is never based on rolling Take-offs. It is always static, so if the #s are close, you know what to do.
 
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Big Picture said:
Just wondering if any corporate operators do reduced thrust takeoffs. It was pretty common in my old job (pt. 121) but I haven't seen it used since I went corporate.

We have a Falcon 50 on MSP Gold and I couldn't tell from the Honeywell website if there would be any financial incentive for an operator to do reduced thrust t/o's.

Any comments?

I've been in the Gulfstream GIV and GV aircraft for 12 years. Probably 99% of the takeoffs we use FLEX.

Exceptions would be wet runway, short runway, high altitude, heavy MGTOW and other such considerations (windshear comes to mind).

Rolls and Gulfstream say to use Max Rated at least every 100 takeoffs. The above scenarios usually make that.

The primary reason for using FLEX is really that it is smoother and less exciting for the folks in back. Max EPR takeoffs with all that power on the back end can be quite exciting and action packed, especially if you happen to be light.

The "gotcha" is that during your effort to make a smooth power application, you have to make sure you set your auto-throttles before you hit 60 kts. GS, or your auto-throttles will "latch" at a lower power setting (hence one of the PNF calls "Power Set")
 
Every leg I am able. No sense wearing out good motors for no reason. ALT T/O unless higher thrust is necessary. Same for Climb. I use the lower climb setting unless ATC asks for something more.
 
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We do reduced power take offs on every take off in the DA-20. Except for Wednesday and when max power is needed for performance requirements.
 
I do not believe there are flex t/o numbers for the Falcon's. There is a selection available for climb though...correct me if I am wrong.
 
2EASYPilot said:
I do not believe there are flex t/o numbers for the Falcon's. There is a selection available for climb though...correct me if I am wrong.


EVERY takeoff is a reduced thrust takeoff in a Falcon.


:eek:
 
Did them in a Lear 35 all the time. You needed to meet 5 items before you could do it, and I can't remember them all, but it was like 6000' dry, less than 15,000lbs, and then you worked backward on a chart, the N1 ended up being around 90% as opposed to 95-96.
It was a freight operation with a lot of hours so it was valuable to the company in this case.
 
From what I understand R/R requires you to use it on the G5, unless conditions dictate otherwise. Your trend and monitoring data is sent to them by your maint folks. From what I was told, if they see excessive rated t/o's where flex could have been used, they can adjust your price accordingly.

The box knows all
 
Gulfstream 200 said:
yup, my box knows all.....just ask her.


:D

I did
 
Give it up for G200, everybody! He'll be here all week. Don't forget to tip the staff... :D TC

P.S.--I'm about the only one who does FLEX in my dept. I guess we don't keep them till overhaul anyway. :rolleyes:
 
You left out the part about two shows on Wednesdays and Sundays

For those of you with alittle extra cash, I am available for weddings and bar mitzvahs.
 

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