Date: 202112
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: IMC
Weather elements / visibility: Icing; Windshear; Turbulence
Aircraft: Medium Transport
Operator: Air Carrier
Operating under: Part 91
Flight plan: IFR
Flight phase: Landing
Airspace: Class D ZZZ
ATC / advisory: Tower ZZZ
Reporter organization: Air Carrier
Reporter function: Check Pilot; Pilot Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown
Second reporter function: First Officer
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Loss Of Aircraft Control; Ground Event / Encounter Weather / Turbulence; Ground Excursion Runway; Inflight Event / Encounter Weather / Turbulence
Result: Flight Crew Regained Aircraft Control
Contributing factors: Weather; Airport
Primary problem: Airport

Narrative: Upon landing in ZZZ Runway XX in strong gusty crosswinds from the left with reported wet runway of 555; the aircraft exited the left side of the runway with the left main gear and the nose gear. The right main remained on the runway surface. The conditions at the airport were rapidly changing from convective activity and rain over to ice/ snow conditions. At the time of the landing only rain was reported. 4 minutes after landing weather was reported as wind 290 at 34 gusting to 48 2 1/2 miles in light freezing rain and mist 800 overcast temperature 1* dew point -2* altimeter 2914. The last report we had received just a minute prior to landing was wind 290 at 25 gust 39. This was from the tower. This equates to 26 kts crosswind and well within the limitations of the aircraft for a runway condition of 555 which was the last report 30 minutes prior. The weather had been studied and determined to be acceptable prior to take off. It was going to be potentially challenging due to convective weather moving out and a cold front moving in; but it was determined that the conditions were within the limitations of the aircraft. The temperature was falling rapidly with the fast approaching cold front from the time of the runway condition report unknown to us at the time. Despite landing upwind wheel first; applying full aileron into the wind; full right rudder and right brake while applying maximum reverse the aircraft turned and the slid towards the left side of the runway. No amount of effort on my part would bring the aircraft back into alignment with the runway centerline. Some differential power was even applied towards the end of the event as a last ditch effort to remain on the runway; to no effect. If the runway had become contaminated with ice prior to landing the crosswind limitation would have been exceeded due to runway contamination. It is my belief that this in fact did happen. I observed ice pellets or similar on the windows while taxiing after the event. When the aircraft exited the paved surface it did so at a very low speed in my estimation. Low enough that applying the right brake should have had the desired effect well before this and significant effect at such low speed; yet it seemed to have no effect at all. Possibly the anti skid was doing it's job but on an icy surface reducing the braking ability. Once we came to a stop half on half off runway edge we notified Tower of our condition. I took a minute or so to rerun the events in my head and access the condition of the aircraft. I saw the runway light go by as we went off the edge. I had heard no impact nor did I believe we ran over the light. The aircraft was not tilting significantly indicating to me that we had neither sank into mud or blown a tire or collapsed a gear leg. The departure from the runway was surprisingly gentle with no abrupt drop off. Based on these observations I decided to see if the aircraft would taxi back onto the runway surface. At first I encountered the takeoff config warning when I added power since we were not in the takeoff configuration. After figuring this out I then had the FO (First Officer) pull the yoke back full to lighten the nosewheel and proceeded to add power to see if we would move. It did move and subsequently taxied back onto the runway surface with little effort once it started to move. We then taxied to parking without further issues. The approach itself was turbulent and icy. We had level 3s once passing the final approach fix. After we broke out wipers were required due to the rain and they were marginally effective at best. Due to the crab for wind the runway was located behind the center pillar of the windshield. Not ideal and the FO saw the runway first. Maintaining glide slop was difficult as was controlling airspeed. Windshear was present. But it was manageable and not at all unusual at this airport during gusty wind conditions; particularly on Runway XX. So I continued. As we approached for a landing I had sufficient rudder for the winds and decided to continue to a landing. As near as I could tell we landed aligned with the runway and the FO also remembers that as well. Due to ice and 13 kts gust factor our landing speed was 116 kts at 27000 lbs. normal landing speed is 89 kts at this weight. May have contributed to the subsequent inability to control the aircraft possibly from hydroplaning? Hard to say; but it's fast being that light. In summation I believe that based on the information I had leading up to and at the time of landing that we were well within limitations and were not taking on unnecessary risks. Had I become aware of icing on the runway a missed approach would have been the only option. It is unfortunate timing and very quickly changing conditions that led to this unfortunate event in my assessment. Next time? If there is one; I'm going around or not departing. I truly regret the outcome of these events and recognize my own contribution to what ultimately took place. I used what I believed to be good information and my own experience in this aircraft to make my decision. In this case that was not adequate when combined with the unknown.


Second narrative: During landing on Runway XX with reported winds of 290 at 25 gusting 39 with a wet runway; the aircraft started sliding to the left edge and came to a stop with the left main wheels in the grass; nose wheel just off the edge of the runway; and right main wheels still on the runway. Reported runway conditions were good/wet with a FICON 5/5/5 30 mins prior to landing. 4 minutes after landing; ATIS was reporting winds 290 a t34 gusting 48; 2.5 miles visibility in freezing rain and mist; 800 overcast. These conditions would calculate a 32 kt crosswind. If runway conditions were compromised by the freezing precipitation that had not been reported; it would exceed the crosswind limitation of the aircraft. The Captain landed with the left main wheels first; aileron into the wind; and applied max reverse with right brake; but despite his efforts; the aircraft slid to the left side of the runway until it came to a stop as previously mentioned. I assisted the Captain by holding his aileron wind correction with him. The nose of the aircraft was aligned with the runway after it came to a stop. As best as I can recall; the nose of the aircraft was aligned or nearly so with the runway the entire time. Some weather vaning may have occurred but it was hard to tell due to the rain and wipers on which restricted some forward visibility. The Captain applied differential thrust in an effort to stop the slide but this had no effect from what we could tell as the aircraft continued to slide. The planes right side exited the runway at a slow speed. Even at slow speed the Captain still could not gain traction. His braking inputs also had negligible results. After leaving the runway; the Captain was able to access that the aircraft had not struck any lights and that the aircraft was still in good condition. After communicating with ATC; the captain had me hold the yoke back to relieve some nose wheel pressure and was then able to use power and taxi back on to the runway. During taxi to parking it was obvious that some kind of freezing precipitation was falling as small ice chunks started adhering to the side windows. The approach was turbulent with significant gusts and rain; the ice detector went off between the final approach fix and next step down as I recall. I then completed first visual indication of icing conditions on the checklist; however we noted no significant or notable ice accretion on the plane. Icing speeds were used with full gust adjustment. At 27;000 lbs; icing speeds pus wind adjustment was 116 kts. The Captain and I agreed that the runway conditions must have been contaminated in some way and normal crosswind inputs were ineffective in getting the aircraft to stop sliding.


Synopsis: Flight crew reported a runway excursion due to incorrect weather reporting and FICON; field conditions; failed to indicate rapidly changing conditions.