Sign in to follow this  
Guest zimmerbz

Drag Required??

Recommended Posts

Each flight in SU2 i have gotten drag "required" when I descend. I put all the winds in the forecast page. What does it mean when I get this message? I usually use speedbrakes by hitting "/". Yet I dont know how long I need to have them deployed...the entire descent? Please fill me in. I love this plane!! BRad Zimmer

Share this post


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

DRAG REQUIRED is displayed anytime the aircraft is more than 10 knots above the FMC target speed OR within 5 knots of the Barber poll (Vmo/Mmo) i.e. the RED WARNING BRICKS on the SPD tape. So what this means is, when you are above the airport restriction altitude (250/10000) you will still get the drag message BUT you can let the speed go all the way to Vmo/Mmo before VNAV will be reverted to LVL CH, the FMC DEScent target speed upon a PATH DEScent is for planning or reference purposes only, the FMC will make no attempt to keep the speed, you can however use some boards to slow yourself. Below the airport restriction (250/10000), you will get the DRAG REQUIRED message also, BUT at 15 knots over the target the AFDS will revert to CWS or LVL CH. So best to actively control your speed if it gets away from you below OR you can go SPD DES here which will sacrafice the PATH for SPEED... The FMC is also *condition aware* which simply means if the causing condition is rectified the message will clear itself. I know this is the case for many CDU messages and assume for the DRAG one too. Once you are within the criteria (not over 10 knots VNAV target speed) retract the boards.[h4]Best Wishes,Randy J. Smithhttp://www.precisionmanuals.com/images/betaimg.jpg

Share this post


Link to post
Share on other sites

Open the window and stick your arm out :)Seriously though, I'm not an expert, and I'm sure Randy answered the question well.

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