Jump to content
Sign in to follow this  
Joelrbt93

PMDG 737 speed descent help!

Recommended Posts

Hi guys! I need help regarding on my descent. As i start my descent using VNAV from ToD, my speed getting increase more and more and end up into overspeed. I tried to avoid using speedbrakes unless there's a tailwind. Can anyone help me how to control my descent speed and without using speedbrakes? And one more question! At what altitude is the most suitable to start extending the flaps? Thks!

 

Joel

Share this post


Link to post
Share on other sites

Again I suggest you read the manual.

 

PMDG have their own forum right here on AVSIM under the 'Commercial' section.  Therefore any specific questions you have would best  be posed there.

Share this post


Link to post
Share on other sites

There are two types of VNAV descent....PATH and SPEED.

 

VNAV SPEED is very similar to Level Change and will use pitch to maintain the speed selected in the VNAV page.

 

VNAV PATH will follow a vertical path that is calulated and will observe any altitude constraintsset in the Legs pages. Although it projects a descent speed, and will add power if speed drops, it is up to you to monitor any overspeed, and use spoilers if neccesary.

 

For the PATH to be accurate you need to enter the descent wind projections in the DES page.

 

It is also important for your descent profile to be accurate. If you have unrealistic altitude constraints in the legs pages, the aircraft will be unable to both follow the path and stay at the desired speed. It is simple physics.


Peter Schluter

Share this post


Link to post
Share on other sites

When your descent speed tends to be too much, are you sure your engines are idling?

 

Sometimes it is necessary to anticipate a short descent route and request from ATC a lower altitude earlier than anticipated. Also plan on reducing speed earlier. Use the descent ARCs on the Enhanced Nav Display (EHSI - Enhanced Horizontal Situation Indicator) and take over vertical nav using the V/S on your MCP.

 

A steep descent may be necessary when there are obstacles in your flight path.

 

Are you getting the message DRAG REQUIRED on the FMC CDU?

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  

  • Tom Allensworth,
    Founder of AVSIM Online


  • Flight Simulation's Premier Resource!

    AVSIM is a free service to the flight simulation community. AVSIM is staffed completely by volunteers and all funds donated to AVSIM go directly back to supporting the community. Your donation here helps to pay our bandwidth costs, emergency funding, and other general costs that crop up from time to time. Thank you for your support!

    Click here for more information and to see all donations year to date.
×
×
  • Create New...