Sign in to follow this  
Mango

don't be afraid of high vertical speeds! 1800fpm no!

Recommended Posts

I see posts where people are limiting their climb rates to the default autopilot climb of 1800 fpm, like in a post down the line about flying the A321. Real jets, especially light weight, do climb like fighter jets!! Do not stop them from climbing rapidly at the initial 200 to 250 kias climb up to 10,000. And above that, up to the flight levels, climb thrust usually 88 - 94% or whatever keeps the other gauges from redlining.. is normal, and you take what the vs gives you! In real modeled jets, (the default don't have lvlchg), you climb at the IAS you want, 250 - 300 etc... at the vertical speed you get... often 4000 - 6000 fpm! Don't try to cut that part down.... unless you are having a hard time keeping up with it.... It will settle down to half that or more at FL300 and above.... A light weight 747-400 will easily go up at 6000fpm initially, as well as a 737NG, A321 etc.! I have seen brief 8000 fpm in the real beechjet I fly, and the default LR45 will realistically hit 10,000 fpm initially if light :)Peter / Beechjet Captain near Boston

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

I remember seeing video of an A340 at some airshow climbing nearly vertically which made me marvel at the power of the thing, but wouldn't the pax loose their lunch climbing at this rate.Mike.

Share this post


Link to post
Share on other sites

Actually, and please correct me if I am wrong, I dont think there will be anyone feeling sick with a 6000fpm or any climb rate for that matter provided the climb rate is a constant or near constant. Infact at any constant climb rate you will experience a force of exactly 1g (as if you were not climbing at all)since there is no acceleration.Excessive but constant climb rate may be a problem if the pressurization system is unable to keep up, or if the attitude of the plane is soo steep that your food slips off your table.Kabs

Share this post


Link to post
Share on other sites

What about descend?Should't there be a poiint in FPS where I cannot exceed?What is the normal range for descend rate in a 747?Manny

Share this post


Link to post
Share on other sites

Only thing is, these high FPMs apply only if jet is lightweight. Try that with a near full 747, and lots of cargo, well, good luck...

Share this post


Link to post
Share on other sites

The passenger issue with FPM is the pressure change rate.How fast do people have to unblock / clear their ears and does a rapid pressure change cause other problems.This is usually more of a problem on descent than climb.There is also a preceptive issue with humans. We expect and are comfortable with attitudes which push us back into out seats.We are not comfortable with nose-down attitudes which pull our backs away from the seats.

Share this post


Link to post
Share on other sites

I think the biggest problem is there is still no true IAS hold in FSX. Dial up the desired IAS and altitude, and the AP pitches to maintain the desired IAS.How this has been ignored for so long is beyond me.

Share this post


Link to post
Share on other sites

>There is also a preceptive issue with humans. We expect and>are comfortable with attitudes which push us back into out>seats.>>We are not comfortable with nose-down attitudes which pull our>backs away from the seats.>>I completely agree. What FPM or nose-down angle do you suggest is a good limit as a rule of thumb for passenger comfort?

Share this post


Link to post
Share on other sites

>I think the biggest problem is there is still no true IAS>hold in FSX. Dial up the desired IAS and altitude, and the AP>pitches to maintain the desired IAS.>>How this has been ignored for so long is beyond me.The Wilco Citation X does it. And you'll get some steep climbs as well even with full tanks... ;-)Heiko

Share this post


Link to post
Share on other sites

It varies with aircraft, but most airlines choose less than 2000 FPM for descent.However, FPM has very little place in the real world for larger aircraft on descent and climb - it's is IAS and pitch.The Bombardier Challenger 604 and the Gulfstream 200 which I've been able to ride the jump seat do not use FPM.They set pitch angle and adjust it up or down to maintain IAS.More than 5 degrees nose down appears to be unpleasant to many people.Also remember that normal cruise for most jet aircraft is 2 to 5 degrees nose up, so five degrees nose down is 7-10 degrees nose down to the pax.

Share this post


Link to post
Share on other sites

It's also the direction of the acceleration. It's still 1 G when you stand on your head..

Share this post


Link to post
Share on other sites

I love this form, you end up learning so much more than what was proposed in the original questions :)

Share this post


Link to post
Share on other sites

Hi all,I've said something similar before on this forum and was quickly "put in my place" by someone who, curiously, didn't actually have any airliner flying experience.I completely agree with the original poster on this issue, it's very very rare to worry about fpm. The only 2 times I can think of is when close to the ground (sets the GPWS off) or when making relatively small climb/descents in a busy TMA (sets TCAS off). Either way, there is an element of protection from those two systems, you would have to be arrogant beyond belligerent to ignore them, not to mention fired.>It varies with aircraft, but most airlines choose less than>2000 FPM for descent.The only restriction in the airline I fly for is that we have to descend at less than 3000fpm when within (or below obviously) 3000ft of the MSA. Apart from that there are no restrictions to our climb/descent rates. The MSA restriction isn't for passenger comfort.The Airbus VSI goes orange when climbing or descending greater than 6000fpm but it won't stop you. I've seen a descent of around 7000fpm and a climb of about the same. Nobody noticed anything out of the ordinary down the back (and believe me they're quick to tell you if they think they do).Any modern pressurisation controller will be able to handle very large rates of climb and descent without any discomfort. Passengers don't really care what your fpm is, only that their beer is cold, their hosties attractive and they arrive on time.>However, FPM has very little place in the real world for>larger aircraft on descent and climb - it's is IAS and pitch.That is correct but we often don't worry too much about pitch, whatever is required to keep the aircraft safe and doing what you want it to do will be fine. The passengers will generally only notice large, quick changes of pitch, roll, slip, engine power (noise) and de/acceleration. Anything else will go unnoticed.I hope this helps,Ian

Share this post


Link to post
Share on other sites

>Hi all,>>I've said something similar before on this forum and was>quickly "put in my place" by someone who, curiously, didn't>actually have any airliner flying experience.>>I completely agree with the original poster on this issue,>it's very very rare to worry about fpm. The only 2 times I can>think of is when close to the ground (sets the GPWS off) or>when making relatively small climb/descents in a busy TMA>(sets TCAS off). Either way, there is an element of protection>from those two systems, you would have to be arrogant beyond>belligerent to ignore them, not to mention fired.>>>It varies with aircraft, but most airlines choose less than>>2000 FPM for descent.>>The only restriction in the airline I fly for is that we have>to descend at less than 3000fpm when within (or below>obviously) 3000ft of the MSA. Apart from that there are no>restrictions to our climb/descent rates. The MSA restriction>isn't for passenger comfort.>>The Airbus VSI goes orange when climbing or descending greater>than 6000fpm but it won't stop you. I've seen a descent of>around 7000fpm and a climb of about the same. Nobody noticed>anything out of the ordinary down the back (and believe me>they're quick to tell you if they think they do).>>Any modern pressurisation controller will be able to handle>very large rates of climb and descent without any discomfort.>Passengers don't really care what your fpm is, only that their>beer is cold, their hosties attractive and they arrive on>time.>>>However, FPM has very little place in the real world for>>larger aircraft on descent and climb - it's is IAS and>pitch.>>That is correct but we often don't worry too much about pitch,>whatever is required to keep the aircraft safe and doing what>you want it to do will be fine. The passengers will generally>only notice large, quick changes of pitch, roll, slip, engine>power (noise) and de/acceleration. Anything else will go>unnoticed.>>I hope this helps,>>Ian>>>>>Coming straight from the mouth of a real commercial pilot! Like others in this post, I was always concerned about this matter of FPM thing and when ever I would see the needle go beyond 2,000 FPM I would adjust, making flying big aircraft annoying and difficult.Great Post :)

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this