Following the GS

[philo beddoe]

As far as autoland goes, I had been told that the last 50 or 100 feet is not done on the GS but uses radar altitude and computed descent rates. This is because the last 50ft of the GS can do some funny stuff.

 

[typhoonpilot]

This is because the last 50ft of the GS can do some funny stuff.

Actually, the aircraft needs to flare so it will usually enter a flare manuever at approximately 50 feet. Following the GS down all the way without flaring might be what causes funny stuff to happen .

TP

 

[FarginDooshbahg]

Dr. Pokenputz needs to pay attention. This thread is about the GLIDESLOPE. You keep referencing the LOCALIZER. Maybe if you put down the MS Flight Sim long enough and read a book, you will understand the difference.

 

[minitour]

be nice guys...

sheesh...I was curious about a VISUAL approach and if you reference or "follow" the GS on that...

no need to get mean with each other...

-mini

 

[Dr Pokenhiemer]

DOOSH,

I WAS talking about G/S. Last time I checked, I dial up the localizer freq. and automatically get a G/S signal also. The post was about the G/S being accurate below DH. I haven't seen MS SIM in several years, just using that as an example before this young gun goes out and tries an IFR ILS to the runway in a real plane just because it CAN be done.

 

[Crosswind79]

Slap the instructor...hmmm - I'll stick with what I was taught, what I currently teach, Avbug, and almost everyone else on this thread EXCEPT for Dr. Know-Nothing....Cat I ILS is not certified down to the runway - thats why the DH is usually 200 feet above the runway ( higher in places like reno and tahoe )...If it was certified to the runway it would be a CAT IIIa or higher. Most of the people on this board know what they are talking about...As for the microsoft pilots, put down the joystick and read 1-1-9 of the AIM. Cat I is NOT usable to the runway for a number of reasons such as local anomalies, glide slope antena location, and aircraft siz and TCH.


There's the computer flying, and then the real world flying.....

 

[Dr Pokenhiemer]

I'll stay on it to DH....After DH, the glide slope is not accurate under a category one approach - only category II and III

I think you missed my point. I was trying to show you that it's the same GS for a CAT III approach as it is for a normal ILS. The only difference is YOUR certification or authorization to use CAT II or III. I believe you said the GS is not accurate below DH."

 

[Crosswind79]

I did say that its not acurate below DH...


ON A CATEGORY I APPROACH.....

If your shooting a CAT II or CAT III then the wx is probably pretty crappy in which case your going to follow the glide slope down to alert height or to the runway, depending on the type of approach your using. But if its a CAT I approach fly it to the DH and don't rely on anything below DH.

 

[avbug]

And said so incorrectly.

Is the glideslope inaccurate for a category I approach below DH? Almost certainly, yes. That, however, is irrelevant. It is not legal for use. The glideslope isn't flight checked nor approved for use below DH.

It's not a matter of accuracy. In most cases, it certainly is. However, it's a matter of legality; the GS isn't approved for use below DH. You can use it as a supplement to visual guidance beyond that point, and should remain at least above it until you have acquired visual vertical guidance.

 

[side stick-n]

Gotta chime in here. If it is not legal to use the GS below 200' on a CAT I approach, then please explain how it can be legal to continue below minimums to 100' above the TDZ with only the approach light system in sight. Uh, what do you plan to use for vertical guidance between 200' and 100'?