Aircraft do not reduce speed on descent

Hi,

got few aircraft which when descending (even with low rate of 1200 fpm) do not slow down even when the throttle is cut. The speed might be too high to deploy the flaps. Let say descending from 15000 to 10000 slowing down from 310kt to 250kt. Do no seem to achieve it with the throttle cut and aircraft continues with 310 or reducing just slightly. Obviously want to hit 10000 with 250 and do not want to use the speed brakes.

Is there any adjustment in aircraft cfg to reduce the speed during descent (drag) before the flaps are deployed?

Any advise much appreciated.

Thanks,

Peter

In this situation, speed brakes are a must. You can deploy them in 10 second intervals to keep the nose from trying to point upwards. This is done in RW aircraft all of the time to help the pilot slow the aircraft.

Peter - I've noticed that the Airbus line of aircraft are much harder to manage descent vs airspeeds! Like Mr Z said, sometimes (or most times as in my case of the Airbus) speed brakes are a must! Boeing doesn't seem to be that bad! What you can do, is plan early in the flight, dropping your airspeed some before your descent begins! You will still have some airspeed to deal with but it won't be as much!

 

Another thing that's frustrating, you deploy the spoilers, the airspeed drops to the point where you can start extending your flaps, everything is going great, you release the spoilers, and the airspeed begins to go back up! Dropping airspeed will help the rate of descent as the N1 level will come down when AT recognizes the reduction in airspeed. You won't lose that much airspeed, as the increase in descent will take care of giving that back to you!

 

I don't think there is any easy way of doing it, other than a "mix and match" of what you have in front of you! I just pay attention and make notes to myself what works best for each line of aircraft. That will make it easier the next "go around!"

 

Peter, I am not an expert at this at all. Never flew anything beyond a Beech Debonair in the real world!

FSX gives me the opportunity to see what I missed all these years! The real pilots who fly these everyday obviously utilize onboard computers to control their aircraft! All we have, is the hunt and seek to see what works for us!

 

Happy flying and have a good evening! - Rick

Thanks gents,

appreciate your feedback. The reason why I asked about aircraft.cfg is because I noted that some aircraft slow down when descending with throttle in idle (no flaps or speed brake) and some don't. I did lot of tuning in aircraft.cfg in different aircraft to adjust the pitch and similar, so thought that some figure there could also affect the speed reduction. In the meantime I will be using the speed brake.

Thanks again,

Peter

Thanks gents,

appreciate your feedback. The reason why I asked about aircraft.cfg is because I noted that some aircraft slow down when descending with throttle in idle (no flaps or speed brake) and some don't. I did lot of tuning in aircraft.cfg in different aircraft to adjust the pitch and similar, so thought that some figure there could also affect the speed reduction. In the meantime I will be using the speed brake.

Thanks again,

Peter

 

Peter- Remember the flying lessons we have had when the instructor told us to always remember the following:

 

Throttle = Altitude

Yoke=Airspeed

 

Somewhere where the two meet, is the problem we are faced with trying to fly these flight sim aircraft! Speed brake is a great tool and that is why they have it installed on these aircraft! I'm with you, I don't use it, unless I absolutely have to! More often than not, in the situations that you described, flying an Airbus, you will be using that speed brake! With the Boeings, I can generally plan ahead and get rid of a lot of un-needed airspeed prior to descent! There is no programming or simple fixes on this!

 

Rick

I don't know if your aircraft is equiped with an FMC on board, but I Always control the whole flight with this small board computer. Never had to use the speedbrakes in 15 years. Simply put in the Alt and speed in the FMC and the board computer will do all the rest. Normally the speed is dropping fast at FL 110 ft to 240 knts so it's below 250 knts when it reaches FL100. Just a tought!!

Another option is to edit the [flight-tuning] section in the aircraft.cfg. Look for the entry:

parasite_drag_scalar=1.0

The figure 1.0 means 100%, you can increase this in 10% increments starting with:

parasite_drag_scalar=1.1

Increasing this figure too much will mean the engines have to work much harder and fuel consumption will increase in proportion, this is one setting where 'just enough' is plenty!

I don't know if your aircraft is equiped with an FMC on board, but I Always control the whole flight with this small board computer. Never had to use the speedbrakes in 15 years. Simply put in the Alt and speed in the FMC and the board computer will do all the rest. Normally the speed is dropping fast at FL 110 ft to 240 knts so it's below 250 knts when it reaches FL100. Just a tought!!

 

How nice! I have FMC's on some of my aircraft, but never learned how to put them to use! I don't know about Peter, whether his aircraft has FMC's or not?

 

Thanks, some day, some week, maybe this week, suuposed to rain here in Sunny South Florida for a solid week! And, hurricane season is just around the corner!

 

Thanks - Rick

Another option is to edit the [flight-tuning] section in the aircraft.cfg. Look for the entry:

parasite_drag_scalar=1.0

The figure 1.0 means 100%, you can increase this in 10% increments starting with:

parasite_drag_scalar=1.1

Increasing this figure too much will mean the engines have to work much harder and fuel consumption will increase in proportion, this is one setting where 'just enough' is plenty!

 

Thanks Tim, not sure I want to mess with these settings! Oh, and I love your signature, "The older I get, the better I was......"

Thanks Tim, not sure I want to mess with these settings! Oh, and I love your signature, "The older I get, the better I was......"

 

Well, if it ain't broke as they say... I can't remember where I got the signature quote from, but it gets truer every year!

Well, if it ain't broke as they say... I can't remember where I got the signature quote from, but it gets truer every year!

 

I've noticed that the longer the time is between when any event occurred and now, caught fish somehow get larger, old batting averages get better, girls I dated get prettier, etc. etc.;)

 

Rupert

Hi gents,

Had good laugh at your posts.

On FMC, yes just like Downwind66 got them installed on few aircraft but never used them.

On aircraft cfg. Thanks for the hint on parasite_drag_scalar Tiger, will test it. But in the meantime someone mentioned that the fuel_flow_gain increase and thrust_scalar reduction helps to slow aircraft at descent. So gave it a shot (adjusted both marginally) and it appears that the aircraft is slowing down on descent more realistically.

Peter