managing descent in twin

[Robert1936]

Can any kind pilot (real or virtual) tell me how to manage descent in the Carenado Navajo? On the approach I can settle on a steady 800 ft per minute, or 500, to catch the glide slope. No problem. But this is at 115 knots. This surely is no way to descend from 20,000 ft and wouldn't be popular with ATC anyhow!

800 f.p.m. is probably OK, but not at this speed. However at 120 to 140 knots, pitch control always seems to revert to level flight after a short interval.

Am I missing something - can you lose height (in a controlled way) without substantial speed reduction, AP or hand-flying?

 

Robert

[mallcott]

Can any kind pilot (real or virtual) tell me how to manage descent in the Carenado Navajo? On the approach I can settle on a steady 800 ft per minute, or 500, to catch the glide slope. No problem. But this is at 115 knots. This surely is no way to descend from 20,000 ft and wouldn't be popular with ATC anyhow!

800 f.p.m. is probably OK, but not at this speed. However at 120 to 140 knots, pitch control always seems to revert to level flight after a short interval.

Am I missing something - can you lose height (in a controlled way) without substantial speed reduction, AP or hand-flying?

 

Robert

 

The way I do it is to peg the speed to the top'o'the'green, then allow the rate of descent that prevents IAS passing that level.

 

The key is begin by pulling back on the power and allowing IAS to decay before increasing the rate of descent. Aviators says `Slow down or Go down, you can't do both at once`, so separate the functions...

[lnuss]

If you're manually easing the nose down to descend with little or no power reduction, your airspeed will, of course, increase. This generates additional lift which will tend to level you off again.

 

But, given the generalities in your post, you might give a bit more detail on how you are trying to descend, not only manual/autopilot, but starting altitude and airspeed (at least for an example, approach or descent from altitude -- they're different), any trim changes or power reduction or stick/yoke pressure, AP settings (if applicable), etc.

 

But note mallcott's post, too.

 

I ask this because procedures can differ a LOT, depending on configuration and exactly what you are trying to do (that is, beyond just descend).

[Robert1936]

Many thanks, both, for the replies. I am normally descending from cruising height and preparing to make the transition to an approach. Sometimes using AP, sometimes hand-flying. I have found it quite tricky to hit the correct height - either finding myself prematurely low, or flying over the runway at 1000 feet. I will follow Mallcott's advice in the first instance -- and just keep practising.

 

Robert