Onboard Performance System...would that be like in your FMS? and you can just select gear down for second segement to give you a new V2 speed that you load into the tapes, and actualy get a new climb gradiant that you check againt the SID? IF so...thats great, I would like to know which FMS your using..having used Collins, Honeywell, NZ2000s...I would very much like you show me how to pull up that info. Thanks.
Given that I have never heard of second segement numbers being calculated for gear down until clear of obsticles, I would really like to learn more about this.

No, it wouldn't. Not in the FMS, nor "like in the FMS."

Too bad. You probably never will. You don't have this capability on your microsoft flight simulator?

Oh, well...since it's not in the FMS, and not in my Part 25 manual...I am still wondering where those second segment gear down climb gradient numbers are?

Whereas lookforshooter has been banned, look for nonflushinglav now...it's his new name. Same poster, same tired rhetoric.

For the record, there's no Part 25 manual. A transport category airplane is certificated under Part 25...but it's not a part 25 manual, nor does it make implication regarding what other aircraft types, or Part 25 for that matter, utilizes for performance data.

Then again, one can't expect to find all the relevant data when one is attempting to operate a microsoft flight simulator.

What is an Onboard Performance System, and what type of aircraft is it in?

OPS isn't "in" an aircraft. It's a performance calculation system developed by Texetron, adapatable to various aircraft, and using manufacturer data.

With this system in place of spagetti charts, we can calculate our performance rapidly based on a lot of factors. What OPS does is allow us to use one source and combine every chart and piece of data into one calculation to come up with takeoff and landing data, as well as calculate max takeoff weights based on anticipated fuel burn, etc. It allows input of forecasts and reports, as well as inclusion of Configuration Deviation List items not applicable to a MEL...small things which of their own accord may not mean much, but which can add up to aerodynamic and performance penalties.

This includes gear extended, wet runways, close-in obstacles, etc.

What's important to understand is that OPS doesn't introduce something that wasn't there to begin with...in other words, anything we can do with OPS, we could have done with the manual charts, but in a much shorter time period, with a much higher degree of accuracy and repeatability. It even formats and prints out the data cards. It's faster than tabulated charts (tab data), whiz wheels, slide rules, etc. It's particularly helpful when a runway change, or even an ATIS change, alters the data used in the last calculation.

What I've often done in the past when I haven't had a tool like this to use, has been to carry my own book of the relevant performance charts, arranged in the proper order to allow me to rapidly make performance calculations on the fly; I've done this for each airplane I've flown, big and small.

Some airplanes provide less data than others. However, if one knows that one's performance is far in excess of that required, then minor variances in the predicted gradient are insignificant. Part 25 establishes minimum gradients. Terminal procedures establish minimum gradients and climb criteria based on obstacles, noise abatement, and air traffic control requirements. An aircraft which exceeds these minimum values by a significant number does not encroach on or compromise the minimum numbers when encountering a small degredation in climb performance.

Some manufacturers publish data with wheels down, some don't. A first segment climb ends with gear retraction, however, and where first segment data is published it is relevant.

So far as gear down operations go...it may be left down for many reasons, and a number of manufacturers do include gear down data. It may be a separate chart, or it may be a performance note showing the performance penalty to add for gear down. OPS simply makes it easier and faster to calculate.

SNS3Guppy: I really want that book you would write. As my PPrUNe habits change, I realize that I skip threads and only stop at your posts to read. And then find there is nothing to contribute; and learn. :D

Flightdetent, that's very kind of you to say, but it would become a very one-sided (read boring) conversation if just one of us posted all the time, wouldn't it?. What makes a site such as this great is the diversity of experience, background, and opinion.