LAHSO go-around danger

[TexasAviation]

One of the potential scenarios for LAHSO involves two planes landing on intersecting runways at approximately the same time. That's one of the big reasons LAHSO exists, as I understand it.

So I got to thinking ... what if both aircraft had to do a go-around? Two planes on final to intersecting runways would put them on a collision course if they both had to go around, wouldn't it?

I figure ATC has procedures/spacing to avoid this. Two simultaneous go-arounds are unlikely to happen (unless the airport suddenly closed for an emergency), but it's certainly in the realm of possibility.

This is the kind of thing I'm daydreaming about while waiting on the club's Archer to finish its annual

 

[BillTIZ]

Normally ATC will have staggered arrivals so the aircraft will not meet at the intersection. But the LAHSO keeps one of the runways usable for the entire length, both could be LAHSO also.

Your contract with ATC is to land and hold short. If something happens that you cannot honor the contract, speak up quickly. ATC now needs to assure that the other aircraft will land with no issues, leaving the air to you. ATC will be scrambling and most likely issue one or both aircraft an immediate turn.

If the winds are squirrelly that you think you may not be able land, do not accept the LAHSO.

 

[timwinters]

As an aside, the FAA seems to be scaling back approved LAHSOs. My home 'drome used to offer LAHSO but aren't allowed to any longer.

 

[Kritchlow]

I've seen ugly situations of which you describe.
Fortunately, I have never flown for an outfit that approved lasho. Not sure if that makes me exempt from the danger though.. Not sure if just because we can't do it, a plane on a crossing runway can do it.

 

[rocketflyer84]

LHSO. Just say no.

 

[roncachamp]

LHSO. Just say no.

Yes, a pilot can refuse LAHSO. I've had pilots flying aircraft that were easily capable of landing within the distance available decline a landing clearance with a LAHSO restriction. My response was clearly something they did not expect; an altitude and heading for resequencing instead of a LAHSO-free landing clearance. I believe every one of them then decided that they actually could land and hold short of the intersecting runway.

 

[rocketflyer84]

Yes, a pilot can refuse LAHSO. I've had pilots flying aircraft that were easily capable of landing within the distance available decline a landing clearance with a LAHSO restriction. My response was clearly something they did not expect; an altitude and heading for resequencing instead of a LAHSO-free landing clearance. I believe every one of them then decided that they actually could land and hold short of the intersecting runway.

The pilots were likely initially declining not because they couldn't land in the distance required (length to the LHSO marker is typically still much longer than most small airport runways) but because they don't like the go-around risk raised here.

 

[roncachamp]

The pilots were likely initially declining not because they couldn't land in the distance required (length to the LHSO marker is typically still much longer than most small airport runways) but because they don't like the go-around risk raised here.

And yet they found that risk acceptable when they understood the alternative was resequencing.

 

[rocketflyer84]

And yet they found that risk acceptable when they understood the alternative was resequencing.

Indeed... getthereitis can develop quickly.

 

[Henning]

One of the potential scenarios for LAHSO involves two planes landing on intersecting runways at approximately the same time. That's one of the big reasons LAHSO exists, as I understand it.

So I got to thinking ... what if both aircraft had to do a go-around? Two planes on final to intersecting runways would put them on a collision course if they both had to go around, wouldn't it?

I figure ATC has procedures/spacing to avoid this. Two simultaneous go-arounds are unlikely to happen (unless the airport suddenly closed for an emergency), but it's certainly in the realm of possibility.

This is the kind of thing I'm daydreaming about while waiting on the club's Archer to finish its annual

Just keep your eyes on them and 'see and avoid'. It's not that tough really.

 

[James331]

I'm not concerned with the go around, that said I don't do LAHSO, it puts all the responsibility on me and frankly I just don't NEED to do them.

 

[Henning]

I'm not concerned with the go around, that said I don't do LAHSO, it puts all the responsibility on me and frankly I just don't NEED to do them.

I don't see the big deal with the ones I get. Most of the time the LAHSO intersection is around 5000' down, and most things I fly I can easily stop in well under 2000'.

 

[roncachamp]

I'm not concerned with the go around, that said I don't do LAHSO, it puts all the responsibility on me and frankly I just don't NEED to do them.

All of the responsibility for what?

 

[Sac Arrow]

I really don't see the big deal. I'm sure in 99% of the situations an actual hazard would only be present in the unlikely event where both landing aircraft had to do a go around at the same time.

 

[Loveair]

I accepted a LAHSO at KBHM just last week. I told my CFI. He said as a student pilot you cannot accept a LAHSO. Just say Unable, student pilot. I guess I should have known. I do now!

 

[BillTIZ]

I accepted a LAHSO at KBHM just last week. I told my CFI. He said as a student pilot you cannot accept a LAHSO. Just say Unable, student pilot. I guess I should have known. I do now!

Where is that written? I did not see it in the AIM.
Must be a specific flight school thing.

If there are LAHSO runways in the area, then the CFI should discuss and train the procedures before allowing solo operation at those airports.

 

[asechrest]

Where is that written? I did not see it in the AIM.
Must be a specific flight school thing.

If there are LAHSO runways in the area, then the CFI should discuss and train the procedures before allowing solo operation at those airports.

It's in 4-3-11. Though you could argue it is not a prohibition against it for student pilots.

Student pilots or pilots not familiar with LAHSO should not participate in the program.

 

[BillTIZ]

It's in 4-3-11. Though you could argue it is not a prohibition against it for student pilots.

Thanks, I missed that one line.

But there is a far distance between an instructor saying "cannot" and the AIM recommending "should not".

The instructor should reference the AIM, discuss the pros and cons with the student and a heavy recommendation to not accept the LAHSO.

The student will accept "cannot" as gospel and pass on bad information to others.

 

[asechrest]

Thanks, I missed that one line.

But there is a far distance between an instructor saying "cannot" and the AIM recommending "should not".

The instructor should reference the AIM, discuss the pros and cons with the student and a heavy recommendation to not accept the LAHSO.

The student will accept "cannot" as gospel and pass on bad information to others.

I'm inclined to agree with you. As another data point, I remember my instructor specifically advising me that I could not accept LAHSO as a student pilot, so I imagine this interpretation is prevalent.

 

[rocketflyer84]

Thanks, I missed that one line.

But there is a far distance between an instructor saying "cannot" and the AIM recommending "should not".

The instructor should reference the AIM, discuss the pros and cons with the student and a heavy recommendation to not accept the LAHSO.

The student will accept "cannot" as gospel and pass on bad information to others.

Actually 7110.118 (the FAA Order regarding LHSO) is quite clear that LHSO is not for student pilots.

"Solo student pilots will not conduct LHSO"

And

"When the arriving pilot identifies their self as a solo student pilot that pilot shall not be issued a LAHSO clearance."

 

[Henning]

Actually 7110.118 (the FAA Order regarding LHSO) is quite clear that LHSO is not for student pilots.

"Solo student pilots will not conduct LHSO"

And

"When the arriving pilot identifies their self as a solo student pilot that pilot shall not be issued a LAHSO clearance."

While this I controlling on controllers, it's (7110) not even known by students nor half the CFIs.

 

[rocketflyer84]

While this I controlling on controllers, it's (7110) not even known by students nor half the CFIs.

Agreed.

Just pointing out that when the AIM days you "should not" do it they really mean you should not do it not "we imply that you should likely not do it but if you do it's ok because we didn't say really really no seriously like we'll be really mad and take away your certificate if you do it so don't even think about it"

CFIs telling students not to do it are not spreading their interpretation but telling them the correct course of action. At the end of the day if the AIM clearly says to not do something then don't do it... Don't debate that the language wasn't quite strong enough so maybe you can slip it past

 

[poadeleted20]

Per AIM 4-3-11:

If a rejected landing​

becomes necessary after accepting a LAHSO​

clearance, the pilot should maintain safe separation​

from other aircraft or vehicles, and should
promptly notify the controller.

IOW, if after accepting a LAHSO clearance you do anything other than land and hold short of the intersecting runway, it's entirely on you the pilot to make sure you don't hit anything.

 

[frfly172]

Lahso is becoming less common lately,and when given the tower usually has time separation so the two aircraft,won't meet in the same space if a go around is necessary.

 

[James331]

All of the responsibility for what?

We have restriction on conditions where we can take a LAHSO at work, ether way I have never been delayed by a notable amount by turning one down.

 

[Henning]

Lahso is becoming less common lately,and when given the tower usually has time separation so the two aircraft,won't meet in the same space if a go around is necessary.

I was given a LAHSO on my 709 ride a few weeks ago. Lots of airports like FXE operating 2 intersecting runways, they are still SOP.

 

[flibmeister]

The potential for conflict in these situations (simultaneous go-arounds during LAHSO situations) is not confined to LAHSO. LAHSO really has nothing to do with it-- the same situation exists any time two aircraft are landing on converging runways, whether the runways actually intersect (thus requiring LAHSO) or not.

And, while simultaneous landings on converging runways do present the possibility that two aircraft could go-around at the same time and suddenly need separating, that's rare. Far more common are operations where an unexpected go-around on a landing runway will put the aircraft in conflict with an aircraft DEPARTING a converging runway. Departures are usually rolled indiscriminately in such situations (ie, with no regard for traffic landing on a runway that converges, but doesn't intersect), and a go-around in this situation results in the exact same scenario that the dual go-around scenario does.

Despite the fact that this scenario is far more common and just as "dangerous", nobody seems to worry about it!

 

[poadeleted20]

The potential for conflict in these situations (simultaneous go-arounds during LAHSO situations) is not confined to LAHSO. LAHSO really has nothing to do with it-- the same situation exists any time two aircraft are landing on converging runways, whether the runways actually intersect (thus requiring LAHSO) or not.

I disagree, because when two planes are landing on intersecting runways without one of them being LAHSO-restricted, the controller must ensure adequate separation so they cannot meet in the middle. As such, there should be no conflict if both go around. The real problem with a go-around off a LAHSO is a conflict at the runway intersection, and that is solved by the restrictions on the controllers for clearing aircraft to land on intersecting runways without LAHSO.

 

[Velocity173]

The potential for conflict in these situations (simultaneous go-arounds during LAHSO situations) is not confined to LAHSO. LAHSO really has nothing to do with it-- the same situation exists any time two aircraft are landing on converging runways, whether the runways actually intersect (thus requiring LAHSO) or not.

And, while simultaneous landings on converging runways do present the possibility that two aircraft could go-around at the same time and suddenly need separating, that's rare. Far more common are operations where an unexpected go-around on a landing runway will put the aircraft in conflict with an aircraft DEPARTING a converging runway. Departures are usually rolled indiscriminately in such situations (ie, with no regard for traffic landing on a runway that converges, but doesn't intersect), and a go-around in this situation results in the exact same scenario that the dual go-around scenario does.

Despite the fact that this scenario is far more common and just as "dangerous", nobody seems to worry about it!

The controller is required to have the departure cross the intersection or turning to avoid in that situation. They're not "rolled indiscriminately." There should never be a problem with an arrival doing a go around unless the controller didn't have approved sep when the arrival was over landing threshold. Even then, a quick application of visual sep would suffice.

 

[flibmeister]

...because when two planes are landing on intersecting runways without one of them being LAHSO-restricted, the controller must ensure adequate separation so they cannot meet in the middle.

True, but my point is that the potential for conflict introduced by the use of LAHSO is not specific to LAHSO; the same potential for conflict is S.O.P. at many other airports (and even on other runway configurations at the same airport).

Consider two airports, both with an identical T-shaped runway layout, with the top of the T being runway 9/27, and the other runway 18/36. The only difference is that at Airport A, the two runways physically intersect; at Airport B, they do not.

At Airport A, without LAHSO, there's no landing on runway 36 and runway 9/27 at the same time-- so you're right, no potential for conflict in the case of dual go-arounds. Airport B, OTOH, can land on their runway 36 at the same time they're landing 9/27, with no regard for what might happen in the event of go-arounds-- so the potential for conflict is there all the time. Using a LAHSO-restriction at Airport A simply puts the potential for conflict at Airport A on par with what already exists at Airport B.

I just find it interesting that the use of LAHSO at Airport A will generate discussion of the "dangers", while the fact that the same situation already exists at Airport B doesn't seem to be a cause of concern.

 

[flibmeister]

They're not "rolled indiscriminately." There should never be a problem with an arrival doing a go around unless the controller didn't have approved sep when the arrival was over landing threshold.

All due respect, but... no.

I'm talking about the situation where departures are rolled, indiscriminately, while arrivals land on a runway that converges toward, but doesn't intersect, the flight path of airplanes off of the departure runway. As long as the arrivals land, all is well-- but if one goes around, the projected flight path of the go-around (unless/until you can get him to turn) will conflict with the departures.

For instance, landing 22R at ORD, with departures off of 28R. One controller will bang departures off of 28R as fast as he can, with total disregard for the arrivals on 22R (which are being worked by a different controller). The runways don't intersect, but if a 22R arrival goes around, he's pointed right at the 28 departures. When it happens (and it does), quick coordination and the application of visual separation saves the day.

That type of operation is routine at ORD, and nobody raises an eyebrow. Throw LAHSO into the mix, though (say, 14R arrivals, holding short of 28R for arrivals or departures), and folks start debating how "dangerous" it is....

 

[Velocity173]

All due respect, but... no.

I'm talking about the situation where departures are rolled, indiscriminately, while arrivals land on a runway that converges toward, but doesn't intersect, the flight path of airplanes off of the departure runway. As long as the arrivals land, all is well-- but if one goes around, the projected flight path of the go-around (unless/until you can get him to turn) will conflict with the departures.

For instance, landing 22R at ORD, with departures off of 28R. One controller will bang departures off of 28R as fast as he can, with total disregard for the arrivals on 22R (which are being worked by a different controller). The runways don't intersect, but if a 22R arrival goes around, he's pointed right at the 28 departures. When it happens (and it does), quick coordination and the application of visual separation saves the day.

That type of operation is routine at ORD, and nobody raises an eyebrow. Throw LAHSO into the mix, though (say, 14R arrivals, holding short of 28R for arrivals or departures), and folks start debating how "dangerous" it is....

Sure, in that case your flight paths do not cross. They can launch guys all day long off rwy 28 while you're on final for 22R. If you happen to go around "N12345, turn right crosswind now for runway 22R." Or they could just restrict you by having you turn crosswind prior to rwy 28.

Every controlled field takes go arounds into consideration. I believe Mark Z works at ORD. He can shed some light on their procedures. I'm sure those guys have got things under control there.

 

[flibmeister]

I'm sure those guys have got things under control there.

They'd better-- I spent 20 years there, both tower and tracon. A few of the controllers, and many of the present management and staff, were my trainees.

Problem is, while most N12345 types have no problem turning a crosswind within the desired boundary, a lot of airline types do-- if the go-around came late (which is often the case), they're low, they're slow, and they ain't turning until things are tidied up (not saying I blame them...). Turning a right crosswind puts them right in the face of the 14R arrivals (often used simultaneously with 22R arrivals). Turning left may put them close to (or in the wake turbulence of) a departure off one of the other runways. Sometimes, depending on the relative location of the departures, it may just be best to let them climb them straight out.

Point is, there's ALWAYS a way to make them miss-- it's just a different way every time (which is why flying "the published miss" is about the most dangerous thing you can do at O'Hare).

But that's the case with every go-around, whether LAHSO is involved or not. Which is why I find the discrepancy in user perception of the safety of go-arounds, LAHSO vs. non-LAHSO (but converging runway) ops, rather curious.