Glideslope and visual approaches

[beytzim]

Good Points. I'll add one more comment. An individual wrote earlier on not to even try to land on that runway if it's too short.

True.

However, many airlines have low speed vs. high speed abort procedures. Usually above 80 knots, one may only abort for certain things, while below 80 knots, you can abort for anything. One may say, if you can't abort for anything prior to V1, you shouldn't go at all. Good, that's my point. Judgement plays a role here - some of us have it, some don't.

Certainly you can abort below V1 for anything and still have enough runway (via BFL numbers). Obviously, the airlines determined that many high speed aborts result in overruns. So they minimized high speed abort for only really serious abnormalities.

Ok, the same thought process can be said about ducking INSIDE the MM. Yes, your numbers say you can easily make it. But, and it's a big but, another 500-1000 never hurts. Big airplanes have the laws of momentum preventing them from ducking - thus the seriousness of unstable approaches. However, airplanes that are small can lower the pitch a little and still be stabilized. Since many corporate airplanes land in short runways (with the same approach speeds as the big airliners), ducking is a required skill.

Fun subject, beer anyone?

beytzim

 

[xrjpilot]

landing distance

For the preflight planning that is required and provided by a dispatcher or the pilot themselves,

the landing distances calculated for a part 25 certified transport category aircraft include

1) crossing the approach end of the runway at 50'
2) on Vref for the weight of the aircraft
3) landing in the touchdown zone
4) using wheel brakes and ground spoilers, NO TR's
5) dry runway

Hope this helps

 

[Focus]

Quack Quack Smack

Ive flown both 135/121 ops. So have alot of other guys/gals who are now flying 121ops. The management that puts the heat on you to deliver in 135 ops without regard to regs. surely is not trying to enhance your career. And believe me, if something goes wrong they will be one of the first to throw you to the wolves.

The debate on who is a better pilot in regard to the operation is totally ludicrous. Its one thing to carry some more speed to the runway in extremely gusty conditions where wind shear is a factor, but ducking under the glide slope will really not save you anything. Boeing has done numerous reports on this issue and Im sure if you call Seattle they will be happy to provide you with the info.

Anyone can duck under a glideslope at any given time and subject themselves to many possible violations. All Boeing or any other authority needs to do is pull the Quick Access Recorder, or other pertinent related reference material and you could find yourself in alot of trouble given the right set of circumstances.

Enough on that. I really dont think there is any reason to duck under the GS unless your in an emergency situation and your forced to land on a shorter runway then optimal. If you get to that point you probably made alot of bad judgements in your flight planning so what else really needs to be said. I cant think of anyone who flew by the book and found themselves in this situation.

Subjecting passengers, yourself, ground personnel or even the cargo your flying to these cowboy maneuvers is hardly what I would call customer service. Your only hurting yourself in the long run. Stay Stabilized with a firm landing in icy conditions and you will be all right. Additionally, bring the aircraft to a complete stop on runway in icing conditions before trying to make a turnoff.

Hope this helps.....

 

[AWACoff]

Hold the phone...I may be smoking crack but the last time I checked, Cat 1 ILSs are flight checked to 100 feet above TDZ. How else are you descending once you have met the criteria at DA to go down to 100ft above TDZ? Please tell me I'm not a crackwhore!

 

[Acestick]

This is kind of related to the question.....

When shooting an ILS and breaking out above the DH, you can then land visually...And part 91 does not specify in the TDZ or whatever, so in theory you could go below the glideslope while in VMC...

Just don't do it on a checkride...I was at a seminar regarding rides and the examiners covered many errors they regularly see. And one of the problems that they all agreed on was regarding applicants ducking below glideslope after breaking out around 200 or 300 feet above the DH. Even thought they are in VMC at that point, the glideslope is about 3 degrees, and going below it is not the smartest thing to do, even though it can be done with reasonable safety in a light single ( A really short field and a fast approach speed )

I'm not sure if its considered illegal or not, or if it is directly addressed in the regs or aim...But I do know that it doesn't look good in a ride when you are trying to impress the DE