What Glideslope to Land Numbers?

[atpcliff]

Hi!

Normally, we use the standard 3 degree to the blocks.

My first landing on a short (5000') runway, I did as usual and the IOE pilot suggested landing closer to the numbers.

So, now on 5000' runways, I aim for the numbers and plan to touchdown between the numbers and the 1000' block.

I was wondering, if we have a GS, how to use it?

If you fly a consistent 1/2 dot low, will that lead you to the numbers? Or, do you need to plan 1 dot low?

Any comments, suggestions, opinions appreciated.

PS-I'm very used to landing on the blocks, with most of my airplane time in jets with VERY long runways.

Cliff
GRB

 

[Andy Neill]

I'm guessing that whether you fly a half dot below, 1 dot below, or any greater number of dots below, they will all take you to the fixed distance marker on an progressively smaller angle.

Since you are probably required to fly the glideslope to the middle marker, landing closer to the numbers would require a change of approach profile in the last 100 feet. This issue was discussed extensively in a previous thread.

 

[FlyinBrian]

I agree with Andy. The dots represent degrees, not feet. So if you fly a dot low, you are flying a shallower path, but you are still flying to the blocks.

Flying a dot low may allow you to more easily abandon the glideslope with the runway in sight .

 

[Mickey]

My guess is you are floating too much for the check airmans comfort. If you are visual, fly visual. Don't try to fly the glideslope all the way down unless you are CAT III and want to plant it down solid. What the others said about the glideslope is very true, it only changes angle and not where it ends. Are you flying an ERJ? If you have more questions on the last 200 feet give me a holler.
Good luck and take care.

 

[CRJ_Driver]

TDZ Zone

As long as its in the Touchdown Zone so they say...but I guess not your IOE Captain.

The CRJ-200 floats more than a Bayliner. If you ever notice a CRJ lands something like 2000' down the rwy everytime. Most everybody else lands about 1200' down the rwy. I've noticed at my airline...lots of folks cross the threshold higher than 50' and at V Approach instead of VREF. 5 knots makes a difference and so does thrust reduction. Idle thrust in the CRJ is needed at 50' along with a properly timed roundout and flare to hit the 1000' foot marker.

What I'm saying is ....it's all good to land "closer to the numbers" but as long as its in the touchdown zone, you stop before the end and you smack your touchdown point relatively close....thats all that really matters.

Fly Safely

 

[lear24]

I disagree that flying consistantly 1 dot low will lead you to the fixed distance marker. If you maintain that 1 dot low until you smack the earth, you will hit prior to to fixed distance marker. The only combination of altitude and glide slope needle indication that meet at the fixed distance marker are the elevation of the marker and on glide slope. If you disagree, land prior to the fixed distance marker and glance at the glide slope indicator as you roll past the fixed distance marker, it should transition from showing low, to on slope, to high until it wigs out a little past the antenna. No matter which way you slice it, you must get the glide slope needle to the center in order to touch down at the right spot, maintaining one dot low will drive you into the ground prior to the fixed distance marker.

Stating that the CRJ always lands 2000' down the runway is kind of silly. Sounds like poor technique you're watching. Every airplane is capable of landing right where you want it, unless you carry too much airspeed, thrust, or flare too high and too long, etc, like you said. It takes experience and practice, but there's not reason that a certain type will always land long.

Fly safe guys.

 

[lear24]

I disagree, it is simply not correct that if you fly one dot low you will end up meeting the earth at the fixed distance marker. You will hit the ground prior to the fixed distance marker if you maintain one dot low until ground contact. Angle matters, sure, but that angle meets the ground before you get to the antenna.

CRJ's may be prone to floating, but saying that they always land 2000' down the runway comments on poor technique. Every airplane can be landed where you want it if you do it right.

Fly safe guys.

 

[DoinTime]

The AIM states that the glideslope is unreliable below the published DH so observations of glideslope indications while rolling by the antenna on the ground are also unreliable. One dot low is approximately 0.2 degrees low which equates to 13.3 feet low at the MM and 3.3 feet low over the threshold. Flying one dot low will get you on the ground closer to the numbers but only by a few feet.

Glideslope antennas will not always bring you right to the fixed distance markers either. They can be mounted from 750 ft. to 1250 ft. down the runway.

 

[atpcliff]

Hi!

Thanks for all the advice and suggestions.

I am flying a Falcon 20, which is very easy to land. You don't really have to flare at all, if you don't want to, just pitch up slightly, and slam it down wherever you want. It has carrier (trailing link) landing gear and will make a nice landing out of a high decent rate.

Usually, these 5000' runways we go to don't have inst approaches to them, so it's a visual manuever. My IOE capt was worried about the winter, icy runways, etc. and wanted me to get it on the ground prior to the blocks.

We're supposed to be at Vref at the threshhold, and I've been tending to be more like ref+5, so I'm working on that.

This morning (night) I landed on a 75' wide runway that was 5000', with a 3.5 glideslope. I touched down just past the blocks, as usuall. The 3.5 made it more difficult, so I'm glads the winds were calm as the other runway was 4.0 glideslope. I landed right on centerline, but the runway sure seemed narrow. At home, the 150' runway with lots of lights was VERY nice.

Cliff
GRB