Jet pilots - question about glideslope adjustments

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Hiya ladies and germs,

I’m an instrument-rated private pilot. So I get the whole pitch/power thing. All of my real-world time is in piston singles. I’m now flying jets for the first time, specifically the wonderful CRJ from Aerosoft. And for the most part I’ve found it quite easy to land. I think a lot of the reason for that is because it does not have an autothrottle, so you always have to manage the power.

I’m pretty darn good at crossing the FAF at VRef+5 and the generally minus 700-750 fpm required to maintain the glideslope at 140 knots, but my specific question is, how do you make adjustments for minor glideslope deviations? If you get half a dot low, is it better just to pull the nose up ever-so-slightly as opposed to adding a hair of power? And if so, at what point does the strategy shift from a slight (and I do mean very slight) pitch up to recapture vs. “okay, now I need to nudge the power a bit”? A full dot?

And I’m not talking about a trending deviation where I’m getting lower and lower on the glideslope. Just a steady state half a dot or dot low.

I’m talking really fine-tuning here. Generally I find about 61-62% N1 is perfect for the final approach segment, on speed and on glideslope. But I was making an approach yesterday and got a full dot low on the ILS (in the CRJ there are two dots above and two below, each representing one degree, not sure if that’s typical of jets or not, vs. most GA aircraft that have 5 above and below, each represnting two degrees). I pushed the throttle up to about 64-65%, and once the engines spooled up to that number the approach basically flattened out and I wound up high. Then I pulled it back to 60% and let’s just say I was imitating a favorite maritime animal down final.

The other thought I had is that perhaps it’s best to nudge the power up for a second or two, but not wait for the glideslope to react and just return the power to where you had it? E.g. I’m a half a dot too low with N1 at 62%, so just nudge it up to 64% for a second or two and then drop it right back to 62. Maybe that will give me the slight correction that I’m looking for?

So that’s essentially my question: when you get a little low on the glideslope in a jet, what is the first best option? Just edge the nose up a hair? Quick power adjustment and back? And what about for a bit too high?

Many thanks in advance for your replies.

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The best way I have found is to do a combination of pull the nose up and an increase in power.
Pulling the nose up alone will cause a speed drop, and with flaps extended, the CRJ will drop speed very quickly.
However, it will respond fairly fast to that, and you need to be ready to back off the throttle when you see it starting to get on the slope.
Opposite for too high.

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So a nudge of power, and as soon as you see the needle start to move, put the power back to where it was? That would seem to make sense. The way jet engines react to inputs I tend to think that if you add power and wait until the dot is back on glideslope before reducing it again, by that point you’re going to go right through it.

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Exactly, it sure will.
You have to anticipate it, I should have said back off quickly when you see it start to respond.

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Awesome, thanks a lot!

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I like reading comments like these. One pilot to another offering advice on flying technique. I don’t play with jets often, but I will remember this next time I do. :+1:t2:

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