Date: 201709
Local time of day: 0601-1200
Location: LGA.Airport, NY
Light: Daylight
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
ATC / advisory: Tower LGA
Second aircraft: Commercial Fixed Wing
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: ATC Issue All Types; Conflict NMAC
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action
Contributing factors: Human Factors; Procedure
Primary problem: Procedure

Narrative: We were cleared for takeoff on Runway 31 with traffic arriving on the crossing Runway 22. As soon as the clearance was received; the thrust levers were stood up and the takeoff roll commenced normally. As is normal; I had an eye out for the traffic landing on the crossing runway. I remember the Tower saying the traffic was at two miles; but as the takeoff roll started I could see the landing aircraft clearly. As we accelerated it soon became obvious to me that we were in a constant bearing; decreasing range scenario. I thought to myself that surely Tower was experienced with this and they would not have cleared us if there was any chance we were going to collide; but it quickly became apparent it was going to be extremely close. I thought for a split second of aborting the takeoff but I thought that may exacerbate our chances of colliding on the runway. We were [also] above 80 knots and on a performance critical runway with water out in front of us. The Tower then told the landing aircraft to go around; and I saw the aircraft level off. I don't know what altitude it was; but it looked relatively low.We had a light aircraft with only 30 passengers and the V1; VR callouts came quickly. To my eye; if I rotated then; we would be aiming right at where the go-around aircraft was going to be; so I held off on rotation in the same manner as I would have if doing a wind shear profile. Using that profile I rotated late and lifted off with a shallow angle trying not to be too low; but by then the go-around aircraft was out of view so I was just hoping we had enough clearance. A few seconds later Tower said something like 'that aircraft is now at your six o'clock - no factor' and we continued the climb out per our clearance. My First Officer was simply fantastic. He was heads down monitoring airspeed and the engines while I was looking at the other aircraft and only figured out what was going on when I didn't rotate on his call. He immediately figured out what was happening and supported me in keeping tabs on the traffic.We didn't say anything to the Tower and they didn't mention anything to us. The remainder of the climb out was uneventful. I am pretty sure that if we had rotated on cue we would have potentially hit the other aircraft. Really; the event happened so fast; I had to react and make decisions on the spot. It was the closest I've come to another aircraft without briefing a formation. At 10;000 feet I had to check the instruments and the configuration four times to make sure I hadn't missed something. We were both pretty wide eyed and a bit rattled. I don't think the Tower knew what we had to do; I think they just assumed that the go-around worked out and that was that.This is not the first time there has been a problem with conflicting traffic on a busy airport so I was actually looking out for this type of event. I think that because the weather was so gorgeous that the Tower was pressing things close. The normal call if things are going to be tight is 'line up and wait; be ready to go.' I don't know if this is in the AIM but it is standard practice. If you are given that clearance you hold the brakes and spool up the engines like you are in SNA. This was not [one] of those cases. We didn't know when we could expect to be cleared so we operated normally. It's pretty unexpected to have this from the Tower since they are the experts and normally extremely good. I think with great weather and experienced crews it may be easy to let tolerances drift a little. In this case I think the Tower was not conservative enough with their spacing. I would like to see what our takeoff would have looked like if we did rotate on cue and what our altitude would have been when crossing 22; especially relative to the other aircraft. I would be more than welcome to hear any debrief and or comments/criticisms from our safety department. This incident rattled me for a bit. I am all for learning anything I can from it.


Second narrative: We were cleared for departure on Runway 31 at LGA. As pilot monitoring; I was inside focused on gauges for required callouts. After calling rotate; I heard Tower tell aircraft landing on Runway 22 to go around. Looking outside to my right I saw the traffic climbing toward and above us. I calmly told the Captain; 'Do not climb steeply' as he was rotating. He kept the rotation to a minimum as we saw the traffic pass over and slightly behind us. After about five seconds Tower called and said that we had traffic to our six o'clock position and was no factor.


Synopsis: B737-700 flight crew reported delaying rotation on takeoff at LGA to increase separation from another aircraft executing a go-around on a crossing runway.