C90 question on visual approaches

BVI4Life

Senior Member
Jun 8, 2009
153
0
16
37
PCT
I have a friend who flies for Shuttle America (Mercury) and he called me with a question regarding clearances to visuals. He said he was given something like this from Chicago TRACON: "Mercury 5641 maintain 3,000, cleared visual runway XX approach" His confusion came because he was under the impression that since they cleared him for the visual, he could descend at his discretion. But his check airman (he was on a checkride for captain) told him no, since they were given a clearance limit of 3000. Any idea why this would be issued in conjunction with a visual approach?

I've never worked radar (but will be soon) and didn't really have an answer for him, so thought I might try and poke around here.

Shanks
 

Radium

Epic Member
Jan 14, 2009
1,988
8
38
Random shot in the dark, but prolly due to the planes position, either traffic or maybe a delta in he way... so wanted to no do any extra work till your friend passed over @ 3k... then descend at his discretion.
 

WatchThis

Trusted Contributor
Apr 29, 2010
557
0
16
Arizona
Could ba a local thing to protect pattern entry. I'll maka a guess and say it's an altitude slightly above pattern altitude (maybe for a crossing pattern). What airport is it?
 

otterstrom

Trusted Member
Jun 16, 2008
461
0
16
of NATCA
was it a charted visual? if so there is probably a crossing restriction somewhere. otherwise it makes no sense without a DME restriction... "cross 10 DME at or above 3000, cleared..." its used to protect for something going on under the final.
 

BVI4Life

Senior Member
Jun 8, 2009
153
0
16
37
PCT
Yeah it was ORD. He flies the E170 family and it's funny, because on the very next leg it happened in DFW. It makes sense to have a restriction, like otter said, but all he was given was "maintain 3000, cleared visual" just seems odd to me, especially since it happened at 2 different facilities.
 

turbovela

Junior Member
Aug 17, 2009
115
0
16
The only thing I can think of is that he had to maintain 3000 until FAF, even if it's not a published visual approach. The FAF in this case would be when he commence his final descent from 3000. He would have to make a computation on how far he needs to start descending from 3000 to safely make an approach and landing taking into consideration app speed, VS and a few other things. Just a guess tho.
 

turbovela

Junior Member
Aug 17, 2009
115
0
16
3000 until what final approach fix?
The FAF in this case would be when he commence his final descent from 3000. He would have to make a computation on how far he needs to start descending from 3000 to safely make an approach and landing taking into consideration app speed, VS and a few other things. You can compute what in the charts is referred to as final approach fix. The published FAF for an app is a distance where at a certain alt you can begin a normal descent for a safe app and landing.
 

FM_Weasel

Senior Analyst
Dec 9, 2008
988
7
18
I'm not sure why the controller would use that then. I just don't see how that helps a controller or how they'd even know roughly when the pilot intends to eventually descend the aircraft below 3,000.

So here's my take on it. I've told aircraft "Descend and maintain 3,000, cleared visual approach <runway>." I do this when they're at an altitude that I need vacated right now, but they've already called the field in sight. So let's say the aircraft is at 6,000, and I need him to descend for traffic. He calls the field in sight. I can get it all done with one instruction. Why not just issue the visual approach clearance? Because I feel just issuing the approach clearance allows the pilot to remain at 6,000 on his own terms, which I don't want. I need him out of 6,000 for traffic. Beyond that, I don't care how low he descends, or when he leaves 3,000, since he's on a visual approach now.
 

turbovela

Junior Member
Aug 17, 2009
115
0
16
I'm not sure why the controller would use that then. I just don't see how that helps a controller or how they'd even know roughly when the pilot intends to eventually descend the aircraft below 3,000.

So here's my take on it. I've told aircraft "Descend and maintain 3,000, cleared visual approach <runway>." I do this when they're at an altitude that I need vacated right now, but they've already called the field in sight. So let's say the aircraft is at 6,000, and I need him to descend for traffic. He calls the field in sight. I can get it all done with one instruction. Why not just issue the visual approach clearance? Because I feel just issuing the approach clearance allows the pilot to remain at 6,000 on his own terms, which I don't want. I need him out of 6,000 for traffic. Beyond that, I don't care how low he descends, or when he leaves 3,000, since he's on a visual approach now.
I agree with you, as I read the question my pilot thinking took over from my flying days. I would assume a good final descent distance to the runway from 3000 would be about 4-6 miles depending on whether the airport is at sea level or not. What I mentioned would be a good assumption from a pilots point of view, but now, after reading your post, it does not make sense why work with assumptions on when the pilot is going to begin descent.
 

futureatc1515

Rookie
Aug 13, 2008
51
0
6
chicago
i know at midway the pilots are restricted to 2500 on a visual because vfr traffic in our airspace can only go up to 2000 and it prevents any ifr and vfr collision conflicts and then local will issue the traffic and tell them to descend at their discretion pending traffic
 

otterstrom

Trusted Member
Jun 16, 2008
461
0
16
of NATCA
most glideslopes put 3000 ft at 10 DME.

anyway, im thinking the controller just misspoke or we're missing some info.
 

wilme861

Junior Member
May 20, 2009
121
1
18
I would assume (keyword there) that I would descend to and maintain 3000 (if not already there) and fly the approach visually until a) another controller tells me differently or b) given a landing clearance from the tower (which is actually the same as a if you think about it).

I would think that B is the more likely case in this scenario.
 

FM_Weasel

Senior Analyst
Dec 9, 2008
988
7
18
I can see how this is a very confusing instruction.

Especially since the approach clearance cancels prior issued speed restrictions (unless restated). Seems awfully confusing to issue a limitation of any kind, THEN issue an approach clearance.

I'd be thinking "Uh, so do I maintain 3,000 -or- am I cleared for a visual approach?" Especially when no limit on the 3,000ft assignment was stated.
 

BVI4Life

Senior Member
Jun 8, 2009
153
0
16
37
PCT
FM, thats exactly what he was thinking. And there wasn't any information missing, we had a 15 minute phone conversation about this, so he was very clear on what was issued.

He passed his checkride, so he's not worried about that. Just confused on a clearance that was issued TWO times, from TWO different facilities.

Thanks for all the help guys!
 

boondr

PHD without a degree
Jul 13, 2008
338
2
18
North of the Equator
I often give "maintain at or above 3000 until 10 DME, cleared visual approach runway XX because of the VFR's below Bravo but I don't work at C90
 

BVI4Life

Senior Member
Jun 8, 2009
153
0
16
37
PCT
Yeah that clearance makes total sense to me (and to him) but there was no limit, just, "maintain 3000, cleared visual approach". I'm just going to chalk it up to being a fluke, but the fact that it happened at 2 different facilities is just adding to the mystery, I guess...
 

mbalunda

Epic Member
Jan 31, 2009
2,867
15
38
meatasaurusx works there. Pehaps you can ask him and he'd be able to help out.
 

meatasaurusx

Trusted Member
Jun 19, 2008
369
2
18
Chi-town
I will try to help if I can. Can you find out what runway he was cleared to at ORD? I am not training on arrivals yet, so I can't say for sure why this happened this way. If you can find out the runway then I can probably find a reason for you. Let me know
 

duranme

Senior Analyst
Nov 3, 2009
920
13
18
BUR
was he already at 3000ft?

at LAX we tell arrivals to descend and maintain XXXX, cleared visual approach, basically to just get the guy down if hes higher, we want them to start down instead of hang up for whatever reason (fuel, wake, whatever)