NMAC near SFO

Looks like someone is in for a violation. Very glad that it wasn't a collision!
 
AdamZ said:
So the Aeronica is now a C182
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I heard that on the radio news this evening. Everything is a Cessna, in much the same way as the world looks like a fire hydrant to a dog.
 
Oh how I wish that those newspaper articles could be more accurate.

"the controller allowed the planes to come too close"...right, ATC is flying the planes. And traffic separation in VMC is primarily ATC's responsibility. Idiots; sorry, no better word for these "newspapers".

-Felix
 
stagecoachco said:
Looks like someone is in for a violation. Very glad that it wasn't a collision!
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Yes, specifically, the airliner and the 182 pilot, for failing to see and avoid traffic. Certainly not the controller as he did nothing wrong.
 
sba55 said:
Yes, specifically, the airliner and the 182 pilot, for failing to see and avoid traffic. Certainly not the controller as he did nothing wrong.
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Agree that the TV reporting seems purely speculative, but violating the jet crew for actually avoiding the other aircraft, you've got to be kidding.:rolleyes:
 
wsuffa said:
I heard that on the radio news this evening. Everything is a Cessna, in much the same way as the world looks like a fire hydrant to a dog.
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N9270E comes up in a search as a Chief...

http://www.aircraftone.com/aircraft/models/aeronca-11ac-0191102.asp

They could have gotten close enough to read the N-number... the Champ I did my tailwheel endorsement in (N3370E, oddly enough), has no xponder and big numbers on the fuse.
But they were in controlled airspace, and the airliner's TCAS issued a warning, so the number probably came from a Mode C installed in the Chief.
 
sba55 said:
Oh how I wish that those newspaper articles could be more accurate.

"the controller allowed the planes to come too close"...right, ATC is flying the planes. And traffic separation in VMC is primarily ATC's responsibility. Idiots; sorry, no better word for these "newspapers".

-Felix
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sba55 said:
Yes, specifically, the airliner and the 182 pilot, for failing to see and avoid traffic. Certainly not the controller as he did nothing wrong.
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Actually, yes, the controller was responsible for separation, or in this case, the lack of separation. This happened in B airspace. From what I read/heard about the incident, He launched the 777 and then told the Cessna to maintain visual separation and pass behind the airliner. The Cessna turned, but at that point, there wasn't much the pilot could do to get out of the 777's way.
 
Just listened to the recording from LiveATC. All sounded routine until the pilot of UA reported the TCAS alert. Hard to tell what happened from the recording.
 
sba55 said:
Yes, specifically, the airliner and the 182 pilot, for failing to see and avoid traffic. Certainly not the controller as he did nothing wrong.
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From what I can gather, the pilot of the small aircraft saw and was desperately trying to avoid the airliner while the blissfully unaware airliner pilots continued to bore in on a collision course until alerted by their TCAS.
 
rottydaddy said:
N9270E comes up in a search as a Chief...

http://www.aircraftone.com/aircraft/models/aeronca-11ac-0191102.asp

They could have gotten close enough to read the N-number... the Champ I did my tailwheel endorsement in (N3370E, oddly enough), has no xponder and big numbers on the fuse.
But they were in controlled airspace, and the airliner's TCAS issued a warning, so the number probably came from a Mode C installed in the Chief.
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Old airplanes (>30 years) only need 2" registration letters (see 14 CFR 45.22)
 
sba55 said:
Oh how I wish that those newspaper articles could be more accurate.

"the controller allowed the planes to come too close"...right, ATC is flying the planes. And traffic separation in VMC is primarily ATC's responsibility. Idiots; sorry, no better word for these "newspapers".
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It happened in Class B airspace, where ATC does have responsibility for separation. If ATC authorized the airplane to be where it was then the controller definitely allowed the planes to come too close.
 
Capt. Geoffrey Thorpe said:
From what I can gather, the pilot of the small aircraft saw and was desperately trying to avoid the airliner while the blissfully unaware airliner pilots continued to bore in on a collision course until alerted by their TCAS.
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To give the airliner crew some credit, It's likely the Cessna (?) was in their blind spot... ATC did tell the smaller plane to "pass behind".
I'd also guess that ATC did not want to advise the airliner to turn, as they were still quite low and climbing.
A more conservative move would have been to tell the smaller plane to turn immediately to a specific heading, rather than the vague directive to "pass behind."

Still, you gotta wonder how the Cessna pilot allowed himself to get so close, given that he said he had the heavy in sight. It would have been no big deal to say "I need to turn away to maintain separation; too close to pass behind", then do it, whether ATC thinks that's a good idea or not.
 
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roncachamp said:
It happened in Class B airspace, where ATC does have responsibility for separation. If ATC authorized the airplane to be where it was then the controller definitely allowed the planes to come too close.
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Yes, but a PIC's responsibility to see and avoid in VMC overrides that, even if said PIC must deviate from ATC directions in order to do so.
 
rottydaddy said:
Yes, but a PIC's responsibility to see and avoid in VMC overrides that, even if said PIC must deviate from ATC directions in order to do so.
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How does a pilot's responsibility to see and avoid override a controller's responsibility for separation? How could it be necessary to deviate from ATC instructions issued to insure separation from an aircraft in order to avoid that same aircraft?
 
rottydaddy said:
Yes, but a PIC's responsibility to see and avoid in VMC overrides that, even if said PIC must deviate from ATC directions in order to do so.
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Well, they saw and they avoided. Doesn't that satisfy the legal requirements? My understanding was that we as pilots just have to not hit anybody else. The actual distance requirements fall on the controller, not the pilot. I could be wrong, though.
 
rottydaddy said:
Still, you gotta wonder how the Cessna pilot allowed himself to get so close, given that he said he had the heavy in sight. It would have been no big deal to say "I need to turn away to maintain separation; too close to pass behind", then do it, whether ATC thinks that's a good idea or not.
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He was probably very close to the extended runway center line when the received the instruction to maintain visual separation and pass behind the 777. At that point, there wasn't anything the Cessna pilot could have done to achieve significant lateral separation by the time the 777 reached him.
 
kkoran said:
He was probably very close to the extended runway center line when the received the instruction to maintain visual separation and pass behind the 777. At that point, there wasn't anything the Cessna pilot could have done to achieve significant lateral separation by the time the 777 reached him.
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The 182 has a yoke, right? He could turn away. A 180 would have been a good idea, maybe even a descending 180 (conflicting traffic climbing, you should descend if possible).
How close would you have to get to a heavy in a 182 before you decided you should probably turn, despite being "very close to the extended runway center line?"
FWIW, if it had been me, as soon as I saw that thing climbing out across my intended path, I'd have changed that path immediately, and probably not by turning inside the heavy's path, but away.

I agree that it's possible that there was just no time, between visual acquisition of the heavy and the time it passed, to get far enough out of the way to be legal (probably the controller's fault), but as far as I can tell, he didn't turn at all, and wound up getting very close indeed (Cessna pilot's fault).
 
rottydaddy said:
The 182 has a yoke, right? He could turn away. A 180 would have been a good idea, maybe even a descending 180 (conflicting traffic climbing, you should descend if possible).
How close would you have to get to a heavy in a 182 before you decided you should probably turn, despite being "very close to the extended runway center line?"
FWIW, if it had been me, as soon as I saw that thing climbing out across my intended path, I'd have changed that path immediately, and probably not by turning inside the heavy's path, but away.

I agree that it's possible that there was just no time, between visual acquisition of the heavy and the time it passed, to get far enough out of the way to be legal (probably the controller's fault), but as far as I can tell, he didn't turn at all, and wound up getting very close indeed (Cessna pilot's fault).
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Maybe you need to re-read the links earlier in the thread which quote the NTSB's release:

NTSB Advisory
National Transportation Safety Board
Washington, DC 20594
March 30, 2010
NTSB INVESTIGATING NEAR MID-AIR COLLISION OVER SAN FRANCISCO INVOLVING COMMERCIAL JETLINER AND SMALL PLANE
The NTSB has launched an investigation to determine why a commercial jetliner and a small light airplane came within an estimated 300 feet of colliding over San Francisco on Saturday.
At about 11:15 a.m. PDT on March 27, the crew of United Airlines Flight 889, a B777-222 (N216UA) destined for Beijing, China, carrying 251 passengers and a crew of 17, was cleared to takeoff from San Francisco International Airport (SFO) on runway 28L and climb to an initial altitude of 3,000 feet. The first officer, who was flying the aircraft, reported that after the landing gear was retracted and the jet was at an altitude of about 1,100 feet, the tower controller reported traffic at his 1 o'clock position. Immediately following the controller's advisory, the airplane's traffic collision avoidance system (TCAS) issued an audible alert of "TRAFFIC TRAFFIC."
 The pilots saw a light high wing airplane, an Aeronca 11AC (N9270E), in a hard left turn traveling from their 1 o'clock to 3 o'clock position. The first officer pushed the control column forward to level the airplane. Both crew members reported seeing only the underside of the Aeronca as it passed to within an estimated 200-300 feet of the 777.
TCAS then issued an "ADJUST VERTICAL SPEED" alert, followed by a "DESCEND, DESCEND" alert. The first officer complied and the flight continued to Beijing without further incident.
NTSB investigator Scott Dunham is traveling to San Francisco to begin the investigation.
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roncachamp said:
How does a pilot's responsibility to see and avoid override a controller's responsibility for separation?
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Good question. Aside from common sense (controllers are not perfect; sometimes they say "maintain sep" when it would be more prudent to issue specific headings), it's covered in the FARs. While none say specifially "PIC's responsibility to see and avoid overrides ATC instructions", you will notice that neither do these rules mention ATC having the final word on what is done with the aircraft under their control. The final responsibility is implied directly.

Some apply directly to this incident, some apply generally to your question. Remember, the main purpose of all ATC commands is to provide adequate separation.

Part 91.3:
b) In an in-flight emergency requiring immediate action, a pilot may deviate from any rule of this part...

Part 91.13:
(a) No person may operate an aircraft in a careless or reckless manner so as to endanger the life or property of another.

Part 91.111:
(a) No person may operate an aircraft so close to another aircraft
as to create a collision hazard.

Part 91.123:
a) ... no pilot... may deviate from that clearance unless... an emergency exists, or... in response to a TCAS resolution advisory."



How could it be necessary to deviate from ATC instructions issued to insure separation from an aircraft in order to avoid that same aircraft?
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I was over-generalizing, there... obviously "maintain visual sep" means what it says. I was referring to the fact that the Cessna pilot might have turned without being specifically given a heading, likewise a change in altitude. Technically he'd be doing what he was told ("maintain separation"), but on the other hand, it could be said that he'd be doing something he was not told to do, which is frowned upon inside a Class B.

But by pointing this out you provided another answer to your first question! This controller obviously felt that the Cessna pilot could ensure separation on his own, and understood that it was legal to allow him to do so. But under the circumstances, it was not the most effective measure, obviously. ATC and PIC responsibilities overlap in such a scenario, and IMHO both should be very conservative.



And to address deviations from ATC separation-specific instructions by pilots in general (remembering again that the primary function of ATC is to provide separation), what if ATC gives an instruction that the PIC can see will (or simply might, in his opinion) create conflict? Does he suggest this to ATC, hope ATC agrees with him,and wait until he's given a different instruction? There might be time for that, but not always. The PIC may have to deviate immediately.

Some examples from my personal experience:

Cleared to land, Class D airport. I was the passenger. Advised by tower of faster traffic (turbine twin) at our 6:00, on a longer final, cleared as #2. By the time #2 was seen, it was passing beneath us (#1 approach was a bit high, #2 was a bit low). It worked out OK, but we were still cleared as #1 as the twin passed beneath us, unable to see us in his overhead blind spot, I guess, and probably a bit over- focused on the runway, LOL.

Like this SFA incident, controller and both pilots were in error, but safety, in the absence of a revised clearance from ATC (they were counting too much on the twin being able to see us and slow down accordingly), required the PIC of #1 to deviate (slow down and steepen descent to land behind #2).

Cleared position and hold, Class D airport. This has happened to me as PIC and passenger. PIC of aircraft cleared for P&H looks at the approach path before rolling, and sees traffic on short final. PIC of departing aircraft does not take position. I refuse to believe that to controllers, "P&H" means "you can't really go until this other guy lands"... what happened in both cases was that Tower did not really know how close to the runway the other traffic was. For safety, a deviation from the clearance, without discussion, was necessary, as per a PIC's rights and responsibilities.Had we crossed the hold line, controller and PIC would have been at fault.

Cleared to enter downwind, Class D airport. I was a student at the time, on a dual flight. We knew there was another aircraft of the same type, on downwind, supposedly ahead of us, but when we spotted it, it was directly abeam, on a wide downwind, close enough that I wouldn't call it "safe", especially because they apparently didn't see us (I notified Tower first).

That time, Tower sorted it out by telling the other flight to remain clear of us and extend their downwind, but had things gotten hairier without comment from Tower, I'd have done whatever I had to do to remain safe, even if it meant turning towards the runway midfield or climbing out of the pattern... or some other deviation from ATC instructions. In restrospect, I was too passive- I should have maneuvered away and then explained why. But at the time, I felt it was sufficient to keep an eye on the other plane while waiting for Tower to come up with a solution.
 
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kkoran said:
Maybe you need to re-read the links earlier in the thread which quote the NTSB's release:
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I did read this stuff... OK, it was an Aeronca, after all. Doesn't really matter.


Based on the text in your reply and the recording, here's what I see:

The Aeronca is advised of the heavy taking off. Aeronca PIC says he has it in sight. Heavy has the right-of-way. ATC tells the Aeronca to maintain visual separation and "pass behind him." I don't know what, if anything, the Aeronca PIC did at that point to ensure that this would happen, but it seems that he did nothing that would definitely keep him clear... like turn, or slow down. A Chief can slow way down in a hurry, and turn without using up much airspace at all.

ATC lets the heavy crew know that the Aeronca is at their 1:00, as they're cycling the gear. They start looking. Meanwhile, the Aeronca PIC does not say "I don't see the heavy anymore", so let's assume he still sees it.

The 777 crew still doesn't see him, and although it might be prudent to level off or turn left, they know they have the right of way, they know the Aeronca reported them in sight and was told by ATC to maintain separation (an instruction acknowledged by the Aeronca's pilot), and they really would rather not change what they are doing, because they have just departed in a 777!

Next thing you know, the TCAS is going off, they shove the 777's nose down, and see the Aeronca over their nose at an "estimated distance of 300 feet"!
How can the Aeronca's pilot not be held responsible for this, even in part?

If the Chief pilot never said he saw the heavy, that would be different. Things could be aligned so that he'd get on top of the 777's path before he saw it, definitely.
But he said he saw it.
Even climbing, the 777 is going about twice as fast as he is, and if he pulled the throttle back, the Chief would practically come to a stop. And if a chief flies anything like a Champ, I know you can stand it on one wing and do a nice slow 360 within a few hundred feet. I don't get how he got so close, unless he was passively waiting for ATC to tell him what to do (and I doubt that).

Let me put it this way: if someone told me they got within 300 feet of a 777 on purpose in a Chief, I'd think that was pretty impressive. :D
 
rottydaddy said:
I did read this stuff... OK, it was an Aeronca, after all. Doesn't really matter.
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My bad--I left off the note at the bottom of the NTSB release that said:
Note: The original media advisory indicated that the light high wing airplane was an Aeronca 11AC with the registration number of N9270E. Subsequent information received by the NTSB clarified that the aircraft involved was a Cessna 182 with a registration number of N9870E.
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rottydaddy said:
Based on the text in your reply and the recording, here's what I see:

The Aeronca is advised of the heavy taking off. Aeronca PIC says he has it in sight. Heavy has the right-of-way. ATC tells the Aeronca to maintain visual separation and "pass behind him." I don't know what, if anything, the Aeronca PIC did at that point to ensure that this would happen, but it seems that he did nothing that would definitely keep him clear... like turn, or slow down. A Chief can slow way down in a hurry, and turn without using up much airspace at all.

ATC lets the heavy crew know that the Aeronca is at their 1:00, as they're cycling the gear. They start looking. Meanwhile, the Aeronca PIC does not say "I don't see the heavy anymore", so let's assume he still sees it.

The 777 crew still doesn't see him, and although it might be prudent to level off or turn left, they know they have the right of way, they know the Aeronca reported them in sight and was told by ATC to maintain separation (an instruction acknowledged by the Aeronca's pilot), and they really would rather not change what they are doing, because they have just departed in a 777!

Next thing you know, the TCAS is going off, they shove the 777's nose down, and see the Aeronca over their nose at an "estimated distance of 300 feet"!
How can the Aeronca's pilot not be held responsible for this, even in part?

If the Chief pilot never said he saw the heavy, that would be different. Things could be aligned so that he'd get on top of the 777's path before he saw it, definitely.
But he said he saw it.
Even climbing, the 777 is going about twice as fast as he is, and if he pulled the throttle back, the Chief would practically come to a stop. And if a chief flies anything like a Champ, I know you can stand it on one wing and do a nice slow 360 within a few hundred feet. I don't get how he got so close, unless he was passively waiting for ATC to tell him what to do (and I doubt that).

Let me put it this way: if someone told me they got within 300 feet of a 777 on purpose in a Chief, I'd think that was pretty impressive.
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Here's the sequence and timing of events based on the recording:

11:46 Tower clears UA 889 for takeoff

12:47 Tower issues traffic to N9870E "70E traffic off departure end is climbing out of 500, 777"

12:49 N9870E responds "in sight"

12:54 Tower instructs N9870E to maintain visual separation and pass behind that aircraft

12:56 N9870E responds "70E pass behind it

12:58 UA889 questions tower about traffic "traffic for 889?"

13:02 Tower responds "just ahead and to your right, Cessna has you in sight, they're maintaining visual separation"

13:07 Tower: "UA889 Heavy traffic no longer a factor, contact NORCAL Departure"

13:11 UA889: "Okay, that set off a TCAS, we need to talk"
---------------
Analysis


The 777 was already past the departure end when the tower issued traffic to the Cessna. Hwy 101 is only about 4,000 ft. from the end of the runway.

Less than 20 seconds passed between the pilot of the Cessna reporting the traffic in sight and tower telling the 777 that traffic was no longer a factor. How long does it take to make a 180° turn in a C-182?

The Cessna was approaching the extended runway centerline. Even with a hard 180° turn, he wouldn't have displaced himself significantly from the extended runway centerline since he would have continued toward the centerline during the first half of the turn and at the end of his turn, would have been about the same distance from the centerline as when he began his turn (probably less due to the loss of speed in the turn).

If the Cessna's pilot had said "unable" to the instruction to maintain visual separation, there was nothing the controller could have done to allieviate the situation at that point. He had already screwed up by not taking action to separate the aircraft 15 or 20 or 30 seconds earlier. As it was, the Cessna's hard turn and the 777's TCAS maneuver saved the day.
 
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Add to it the earlier instruction to the Cessna to maintain a position relative to the 101 freeway (about 9:30 in the recording) and the later instructions to the Cessna when departing the airspace.

If I didn't mishear, I also believe the weather calls were for an east wind, which was a slight tailwind on the 777. Whether that afffected actual performance is another question.
 
A control tower mistake at San Francisco International Airport caused a mid-air scare for a commercial flight and a small plane on Saturday.
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The FAA agrees though that the planes were too close together and that the air traffic controller in the tower should have noticed this earlier.
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The FAA says no action will be taken against the air traffic controller on duty that day, but there will be re-training and re-education of staff.
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http://abclocal.go.com/kgo/story?section=news/local/peninsula&id=7359230
 
I read that is was reported as coming within 300 ft vertical but 1500 ft horizontal. Why is it that only the 300 ft is being focused upon? Gee, I guess if another aircraft across the valley is at 5800 feet and I am at 5500 feet several miles away, that can be reported as near mid air collision being within 300 ft of each other! Granted, both vertical and horizontal in this case is a little too close for me. But, still the news reports and facts always seem to get distorted!
 
skidoo said:
I read that is was reported as coming within 300 ft vertical but 1500 ft horizontal. Why is it that only the 300 ft is being focused upon? Gee, I guess if another aircraft across the valley is at 5800 feet and I am at 5500 feet several miles away, that can be reported as near mid air collision being within 300 ft of each other! Granted, both vertical and horizontal in this case is a little too close for me. But, still the news reports and facts always seem to get distorted!
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Faux News mentioned the 1500' seperation but concnetrated on the "less than the distance of a football field separation" (vertical, pretty close to what they said).
 
Cap'n Jack said:
Faux News mentioned the 1500' seperation but concnetrated on the "less than the distance of a football field separation" (vertical, pretty close to what they said).
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We can keep the editorial opinions about certain news outlets out of this. ABC and our local ABC station focused on the 300 feet, too. Their (ABC's) mention of the 1500 feet lateral separation was the first I had heard that fact. Far less alarming than "300 feet". But, whatever sells papers...
 
You do realize that 1500ft of horizontal distance would be achieved in under 6 seconds (assuming a climbout at 165kts) by the B777! :yikes:

I'm still thinking that should sell papers!
 
RedBaron said:
You do realize that 1500ft of horizontal distance would be achieved in under 6 seconds (assuming a climbout at 165kts) by the B777! :yikes:

I'm still thinking that should sell papers!
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I suspect that the climbing 777 was doing more like 200-250 KTAS but the "lateral separation" was likely in reference to the jet with the Cessna/Aeronca 1500 ft to the side of the 777 so the jet's forward speed wouldn't have mattered much and might even have increased the ultimate separation.
 
Once you say you have the other aircraft in sight and can maintain visual separation that's what you're supposed to do. I wonder if the smaller airplane, whatever it was, had some other airplane in sight and didn't see the 777, either that or maybe he didn't judge his closure rate properly.
 
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