ILS or GPS?

[MercFE]

CRJ. It could be hand flown, but it still takes a few seconds to get the nose to pitch over. Otherwise you tend to scare the passengers and they frown on us doing that sort of thing.

My favorite part of military flying... Passengers have no choice!

When you mentioned about 900 fpm for the descent, all I could think of was our standard 1200 fpm descents on NPAs.

Guess I would ask, why not shoot the GPS... Not scaring the pax... And go around for the ILS if need be? I know you run into the money issue then, but if your landing on a "shortish" runway, with a tailwind, and wet... The legal headwind approach sounds like a good call to me.

Actually had a controller ask about the "rides" one time. When we responded with it not being bad, he asked if we would fly in it if we were paying pax... We gave him a different answer.

 

[TUCKnTRUCK]

It's a bummer you don't have rnav/vnav.

My answer, brief it up, fly the rnav. If it doesn't work, take it around and fly the ILS. At least then you'll be a few hundred pounds lighter for the tailwind landing. While it looks challenging, with a good brief, an timely execution it is easily doable.

 

[Polar742]

Run the landing data for both runways, wet, no t/r. Is it legal? If so, GPS approach. Use constant descent technique with good technique (IIRC, the CRJ has the inertial "green banana" and a VTK indication. Couple that with spinning the altitude preselect prior to capturing the altitude).

As SteveC says, if it's not working out as expected (cigs are over mins. I can't remember the last approach where I broke out of solid clouds and had the vis. You'll know if it'll work before you get there) go around. Weather changes, we all know that.

Safe, smart, professional.

 

[ppragman]

No thanks. I make it a goal to have to perform circling approaches at mins only in the sim.

Edit: Also note the minimum circling visibility of 2 miles for Category D.

But in general, a circling approach in a jet where you have to maneuver from downwind to base to final leaves too much opportunity to screw up when you're "low and slow".

Wait what? You mean, maneuvering the jet is too risky? If you screw it up, go missed. I don't really see the problem, but again, I'm a prop guy.

 

[SpiceWeasel]

Wait what? You mean, maneuvering the jet is too risky? If you screw it up, go missed. I don't really see the problem, but again, I'm a prop guy.

We can't legally conduct circling approaches most of the time. My type says "circling approach VMC only". 1000' and 3 mi seems higher than the minimums in this approach scenario. In the CRJ, we have to be at gear down, flaps 30, 160 kts on the circle. Can't fully configure (flaps 45 and reduce to ref) until essentially lined up. Also, our aircraft doesn't have LE devices. Not exactly a great position to be in, low, slow, banking, in a swept wing jet with low WX. Again, there are folks in the back, and heck, on the ground.

Ethan, I ran into this scenario minus the runway length last winter up in the Yoo P. Tried the GPS first, preferring the winds over the minimums, when it didn't work we went missed, and set up for the ILS. We don't have that word of mouth for the .2 lead from our FSDO though.

 

[mastermags]

We use 1500 fpm descents on all the step down fixes and a constant rate with snowflake as guidance at the final fix. Works just fine and doesn't seem to scare anybody.

 

[MoMatt]

Wait what? You mean, maneuvering the jet is too risky? If you screw it up, go missed. I don't really see the problem, but again, I'm a prop guy.

Yeah, I suppose you could classify it as "too risky." For me and the plane I fly it's legal, but pretty discouraged. I think most CRJ operators are limited to VMC only for circling. I see your point that it's just an airplane, but with a swept wing and the lag time for adding thrust in a jet, you don't leave yourself very much room for error. Also, the maneuver itself precludes an honest stabilized approach, which adds to the pile even more when going into a "shortish" runway.

 

[///AMG]

My favorite part of military flying... Passengers have no choice!

While I don't carry pax (or anyone else), my least favorite part of mil flying is that we have neither ILS nor GPS approach capability.....aside from boat ILS (ICLS). Not true for fat kids or helos, but I would have flown yesterday had we been capable of either type of approach, so I am bitter I guess. Then again, I got to cold start the jet two days in a row (including actually aviating today) so I guess that is better than nothing right?

 

[dasleben]

Wait what? You mean, maneuvering the jet is too risky? If you screw it up, go missed. I don't really see the problem, but again, I'm a prop guy.

There have been several fatal accidents caused by circling outside the protected radius in Category C/D/E jets at mins. Not something normally done in 121 ops. And yes, I've done it plenty to mins in the 402; wouldn't attempt it in the 767.

 

[MercFE]

While I don't carry pax (or anyone else), my least favorite part of mil flying is that we have neither ILS nor GPS approach capability.....aside from boat ILS (ICLS). Not true for fat kids or helos, but I would have flown yesterday had we been capable of either type of approach, so I am bitter I guess. Then again, I got to cold start the jet two days in a row (including actually aviating today) so I guess that is better than nothing right?

Yeah, it is interesting actually flying to a Navy field with no ILS. Best we have at Pax is a PAR, with controllers that give you crazy "turn 10 right" calls as you're approaching mins... After an approach or two, it quickly turns into a PAR, with RNAV assistance. It's amazing how quickly "on course" becomes part of their vocab.

It is fun watching the heavy pilots try to figure out how to use the lens system as a glide slope tool, however.

 

[jtrain609]

So a few folks have advocated trying to get in on the ILS if you didn't get in on the GPS approach. My question for ya'll is why?

If you've determined that a tailwind, plus a wet runway to the runway with the ILS is a bad idea because you'll only have 400' remaining if everything goes correctly (and remember, those are the same kinds of numbers that Southwest had when they went off the end of the runway in Midway a few years ago), and you've decided that you want to do the GPS approach instead, why would you go back around and try the ILS?

I mean if the wind changes and you're able to get a little more wiggle room on the stopping distance, that's great, but if conditions remain the same, for my money it's better to divert and wait it out an hour or two than risk sliding it off the end of the runway.

So with that, I know that the numbers say it'll work, and there's a point where we should trust the numbers, but my question revolves more around making one decision, which seems to be a good one, and then walking back on it later "just to get in." In my mind, once you make the determination that the GPS is the superior approach, then you've completely excluded the possibility of doing the ILS under the same conditions.

 

[Roger Roger]

There have been several fatal accidents caused by circling outside the protected radius in Category C/D/E jets at mins. Not something normally done in 121 ops. And yes, I've done it plenty to mins in the 402; wouldn't attempt it in the 767.

Well, and to add to that, I would highly doubt that the ILS circling mins get you any lower than the GPS straight in mins.

 

[SpiceWeasel]

So a few folks have advocated trying to get in on the ILS if you didn't get in on the GPS approach. My question for ya'll is why?

If you've determined that a tailwind, plus a wet runway to the runway with the ILS is a bad idea because you'll only have 400' remaining if everything goes correctly (and remember, those are the same kinds of numbers that Southwest had when they went off the end of the runway in Midway a few years ago), and you've decided that you want to do the GPS approach instead, why would you go back around and try the ILS?

I mean if the wind changes and you're able to get a little more wiggle room on the stopping distance, that's great, but if conditions remain the same, for my money it's better to divert and wait it out an hour or two than risk sliding it off the end of the runway.

So with that, I know that the numbers say it'll work, and there's a point where we should trust the numbers, but my question revolves more around making one decision, which seems to be a good one, and then walking back on it later "just to get in." In my mind, once you make the determination that the GPS is the superior approach, then you've completely excluded the possibility of doing the ILS under the same conditions.

Not necessarily. How comfortable are you with the plane, do you prefer the "easy" way to start or do you automatically go for the hard way. What are the numbers telling you? Runway required vs actually landig distance and all. I think the closest I've ever had numbers-wise for a dry runway, mind you, was 200 ft between available and required.

Can you fly the plane with precision? If you can, and the numbers work out, there should be no question that the approach in either direction is safe and doable. If you "slide off the end", why? Were you outside of company landing standard or did a system malfunction?

Why does it matter that the runway is wet anyway? According to our manuals, you have dry, wet, or contaminated. How do your landing numbers get calculated? We always use wet numbers unless we need the numbers to work and certain parameters to use dry are met.

I'd also like to add that a go around is always an option as is your divert. If you aren't on profile at any point (down to where you are flaring / appearing to touch down), go around.

 

[MercFE]

So a few folks have advocated trying to get in on the ILS if you didn't get in on the GPS approach. My question for ya'll is why?

If you've determined that a tailwind, plus a wet runway to the runway with the ILS is a bad idea because you'll only have 400' remaining if everything goes correctly (and remember, those are the same kinds of numbers that Southwest had when they went off the end of the runway in Midway a few years ago), and you've decided that you want to do the GPS approach instead, why would you go back around and try the ILS?

I mean if the wind changes and you're able to get a little more wiggle room on the stopping distance, that's great, but if conditions remain the same, for my money it's better to divert and wait it out an hour or two than risk sliding it off the end of the runway.

So with that, I know that the numbers say it'll work, and there's a point where we should trust the numbers, but my question revolves more around making one decision, which seems to be a good one, and then walking back on it later "just to get in." In my mind, once you make the determination that the GPS is the superior approach, then you've completely excluded the possibility of doing the ILS under the same conditions.

Agree, in part, with what you're saying.

However, if one needs to shoot the "perfect" approach all the way into the flare for the numbers to support taking the ILS with tailwind, aren't you running the risk of a go-around for something that might not be needed?

If the weather is supporting a GPS approach, with a good chance of breaking out and using the weather to your advantage in getting down first try, why not shoot it?

 

[dasleben]

Certainly not unsafe to take the ILS, rather, more conservative and preferable to take the GPS approach.

EDIT: Just saw the fact that the landing data puts you within 400' of the end...GPS all the way, in that case. An extra 400' is easily lost with a few knots above Vref, or float. It can be done, but not worth it, in my mind.

 

[BEEF SUPREME]

Depends what end I'm parking on.

 

[slemers]

There have been several fatal accidents caused by circling outside the protected radius in Category C/D/E jets at mins. Not something normally done in 121 ops. And yes, I've done it plenty to mins in the 402; wouldn't attempt it in the 767.

JAL used to fly hand flown min circles at Moses Lake with new FO's in the 74. They would never be expected to do it on the line though.
Some interesting flying went on there, stall series to the shaker, steep turns etc.

 

[Tommay85]

Is 400 feet a big pucker factor? I mean, that's more than a football fields worth of runway remaining. Personally, I don't like cutting it close in less than ideal conditions. Just asking

 

[SteveC]

Question: when you guys talk about being within 400', is that factored (60%) or actual landing distance?

 

[dasleben]

Is 400 feet a big pucker factor? I mean, that's more than a football fields worth of runway remaining. Personally, I don't like cutting it close in less than ideal conditions. Just asking

Too close in my mind, when a 3 second float eats up 650+ feet alone.