Jump to content

Sign in to follow this  
Guest

Power fluctuations at idle

Recommended Posts

Guest

I have been noticing strange power fluctuations with the 757. They occur when the throttles are pulled back to idle during taxi. They happen as follows:1. Begin from a still position.2. With the brakes off, increase power to 45% or so of N1 until the plane starts moving. 3. Pull the throttles back to idle in a single smooth motion.4. The power drops off as expected, but when it reaches idle, it momentarily goes back up slightly before returning to idle and staying there. At first I thought it was something with the sound, but when I looked at the engine read-outs, I could actually see the power go back up (only slightly and only for a fraction of a second). Does anyone else experience this? Is this intentional? I admit that I have not looked in the manual for an explanation of this behavior, but I do not remember it happening with the 777.Andrew

Share this post


Link to post
Guest

I have the exact same problem as well. Has done this in the exterior view? When I did it the sound sounded like a grehound bus changing from 2nd to 1st gear at 40 mph. CB

Share this post


Link to post
Guest

Actually I was thinking more like a Volvo Simi with my girl friend trying to do a 3 to 2....Ditto on the Engine surge, mine is mostly with the port engine with the occasional duet from starboard.

Share this post


Link to post
Guest

Well, looks like we have a number of people (if not everyone?) with this happeneing. It's not a very serious issue, as the surging does not interfere significantly with controling the aircraft during taxi, but it is a little annoying. Hopefully, Rob, Lefteris and company will take a look at it when they get a chance.Andrew

Share this post


Link to post
Guest

Just bumping it up again. I would like a comment from someone with PMDG when they get a chance, just so I know it is on their list of things to look at.Regards,Andrew

Share this post


Link to post

Gents-I've been waiting for Vangelis to pick this up, but he's currently really busy with other stuff, so I'll post a somewhat-generic answer:The phenomenon you're noticing is due to the Fly!2 Jet Engine model. The way it's been programmed, you will either experience those momentary fluctuations, or you would be getting idle N1 at 35% (not very realistic, right?). We (as always) went with more realism.Hope this answers (a bit) your questions...

Share this post


Link to post

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  
×
×
  • Create New...