88
votes
How close can planes fly to each other over the ocean?
It was only very slightly higher than our plane by mere meters.
You think you saw a plane at the exact same vertical level as yours, when in fact it was at least 300 metres (1000 feet) above or below ...
- 37k
70
votes
How close can planes fly to each other over the ocean?
This is an excellent question, and helps illuminate several important aspects of the way perception works in aviation. But first...
Any near-miss or other air-proximity incident would have been ...
- 12.9k
25
votes
Accepted
Is the pilot required to keep visual lookout during IFR operations in VMC?
You didn't mention which country or jurisdiction you're asking about, but in the US 14 CFR 91.113(b) says:
When weather conditions permit, regardless of whether an operation is
conducted under ...
- 71.9k
25
votes
Accepted
What will be the immediate action by the pilot and ATC if any plane blocks the runway while landing?
ATC will tell the landing plane to go-around. The pilot will then execute the go-around by flying the missed approach procedure as published in the airport charts.
Go-arounds happen daily and are ...
- 1,880
16
votes
How close can planes fly to each other over the ocean?
A "small" transatlantic plane probably isn't very small -- it was probably further away than you think. Compare these silhouettes (can't embed due to image rights, also can't vouch for accuracy):
...
- 1,157
15
votes
Accepted
Vertical and horizontal separation between cruising and climbing aircraft
I think you may have answered your own question note the use of the word OR
To my understanding, aircraft at these altitudes should always have a
separation of least 1000 ft or 5 nm.
If you ...
- 102k
14
votes
How does a TCAS system avoid unnecessary (RAs) resolution advisories when aircraft are operating on separate closely spaced parallel runways?
The TCAS logic is adjusted when the aircraft is in the terminal area. It does this through the following inputs:
Radio Altitude - Controls TCAS parameters when below 2350 feet AGL
Landing Gear, Flaps,...
- 20.1k
13
votes
Why are both ATC and TCAS tasked to prevent collisions although TCAS takes precedence anyway?
While ATC's primary goal is to prevent collisions, it is also responsible for the efficient movement of aircraft through the airspace. That requires a strategic approach to managing air traffic to get ...
- 20.1k
10
votes
Is the pilot required to keep visual lookout during IFR operations in VMC?
ATC assures separation...
This is a pretty critical misconception. ATC does not necessarily provide separation, just because you are flying IFR. Let's do a quick recap of the different airspace ...
- 37k
9
votes
How is radar separation assured between primary and secondary targets?
Typically the surveillance information from multiple sources (PSR, SSR, ADS-B, multilateration, etc) are combined into a single "system track" using a Kalman filter. The ATM system has specific code ...
- 9,182
8
votes
How close can planes fly to each other over the ocean?
Something to note here would be that modern aircraft contain a Traffic collision avoidance system (TCAS). So pilots in both aircraft would have been notified that they were on a collision and one ...
- 6,233
8
votes
Accepted
How is separation managed when there are only two parallel runways in a very busy airport?
With two runways, usually, one is dedicated to arrivals, and the other is dedicated to departures. That's the simplest way to handle separation -- only in-trail separation is involved.
That's ...
- 126
8
votes
Accepted
Why are both ATC and TCAS tasked to prevent collisions although TCAS takes precedence anyway?
TCAS is sort of a fallback, last-resort system used in case all else fails. TCAS works within the scope of what happens within the next minute or so, and will require the involved aircraft to perform ...
- 37k
8
votes
What will be the immediate action by the pilot and ATC if any plane blocks the runway while landing?
one plane is trying to take off at the end of the runway and other plane trying to land from the other end of the runway
That would never happen. Planes are under ATC control from the moment they ...
- 37k
7
votes
Accepted
Why do heavy departures wait 5-10 minutes on the runway at ZRH?
The usual reason is, that departures from runway 16 are not allowed to climb straight ahead due to noise restrictions over downtown Zurich. Instead they need to turn left, where they cross the ...
- 200
7
votes
Accepted
What vertical separation is required in a holding stack to avoid wake turbulence?
The minimum vertical separation in a holding stack is no different from the minimal vertical separation used elsewhere. This is almost universally 1000 feet. In countries where Reduced Vertical ...
- 37k
7
votes
Accepted
How is radar separation assured between primary and secondary targets?
Mode C transponders only transmit a squawk code (same as mode A) and altitude, so the range error due to slant distance is the same for SSR as for PSR, and the two can be easily merged. Mode S adds ...
- 27.8k
7
votes
How to determine the traffic avoidance manuver?
In Scenario A there is no obvious answer. You take whatever action is necessary to avoid a collision. If this were a controlled airfield there would be questions raised to the ground controller. If ...
- 35.2k
7
votes
Accepted
Which avoidance maneuver is best when seeing crossing traffic on approach to a runway?
When you are on short final and something is on, is entering, or even seems to be entering the runway, you execute a go around.
As for the second part of your question, given the loose parameters I'...
- 30k
7
votes
Why does DME colocated with VOR require more separation?
The change appears to be clarifying that if the 15 NM distance determination is based on ground distance, for example the aircraft has passed a fix which is known to be farther than 15 NM from the VOR,...
- 16.5k
7
votes
What are the separation requirements on the ground?
Except in relation to active runways, the FAA defines no specific minimum separation between aircraft operating on the ground.
JO 7110.65 paragraph 2–1–1 states that "the primary purpose of the ...
- 16.5k
6
votes
Accepted
Can RVSM safely be further reduced?
Reducing further to 500 ft separation is not safe with current aircraft models.
One reason is because of wake turbulence, this is described by ymb1's answer. Another, perhaps more compelling reason, ...
- 83.8k
6
votes
Accepted
What does "leave clear on its left" mean in UK regulations relating to collision avoidance on non-runway landings?
Seems understandable to me.
It may be more clear with commas...
"(a) when landing, a flying machine or glider must leave clear, on its left, any aircraft which has landed, is already landing or is ...
- 126
6
votes
Accepted
Is true altitude vertical separation between airplanes dependent on temperature?
Yes, the vertical geometric separation is temperature dependent.
If it cooler than ICAO Standard Atmosphere (ISA) conditions, the geometric vertical separation is lower than the pressure altitude ...
- 83.8k
6
votes
Accepted
Why do planes above FL290 need more vertical spacing?
The atmospheric pressure changes more rapidly with altitude near the ground than it does higher up. Assuming an instrument has some error based on determining the difference between two pressures, ...
- 5,901
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