TWR ratio >1, yet decelerating?

[bisto]

Should this happen? I use the engineer mod in the VAB. My first stage, after SRB seperation, consists of 6 liquid tank stacks feeding to a central stack of the same size. The engineer mod tells me my kerbin TWR is about 1.6 for this stage, yet still decelerates when the outer 6 tanks drop off, until some fuel is burnt off. Can anyone explain?

[Kellis]

How fast are you going, and at what altitude? It's possible that your engines can't overcome atmospheric drag. Really low in the atmosphere, 150m/s takes some doing, though it gets better pretty quickly..

[Ziff]

Post a picture of the craft file, or the .craft file itself. I'm going to guess that your staging setup is confusing the T:W ratio in Kerbal Engineer mod causing it to report the wrong T:W ratio for that stage.

[phoenix_ca]

Post a picture of the craft file, or the .craft file itself. I'm going to guess that your staging setup is confusing the T:W ratio in Kerbal Engineer mod causing it to report the wrong T:W ratio for that stage.

Most likely case. I suggest using MechJeb to confirm what your current TWR is at that point, because it gives you an updated TWR at all times in the Vessel Information panel.

[Ziff]

Most likely case. I suggest using MechJeb to confirm what your current TWR is at that point, because it gives you an updated TWR at all times in the Vessel Information panel.

This is exactly why I use MechJeb. It is absolutely invaluable for its instant relay of important information. Apoapsis, Periapsis, true altitude, vertical/horizontal velcocity, T:W ratio, current craft weight, all extremely valuable information. This is great advice.

[Kosmo-not]

Should this happen? I use the engineer mod in the VAB. My first stage, after SRB seperation, consists of 6 liquid tank stacks feeding to a central stack of the same size. The engineer mod tells me my kerbin TWR is about 1.6 for this stage, yet still decelerates when the outer 6 tanks drop off, until some fuel is burnt off. Can anyone explain?

This is due to your rocket having a greater TWR just prior to the separation compared to just after. In this case, your rocket will slow down a little. This is due to atmospheric drag and is normal.

[EndlessWaves]

This is due to your rocket having a greater TWR just prior to the separation compared to just after. In this case, your rocket will slow down a little. This is due to atmospheric drag and is normal.

The rate of acceleration will slow dropping to a lower TWR but the actual velocity will only stop increasing if you can no longer overcome the drag.