Flight Details
Aircraft Type: Bombardier Canadair Regional Jet CRJ-700
Operator: SkyWest Airlines on behalf of United Airlines
Registration: N718EV
Flight Number: UA-4748
Route: Chicago O’Hare International Airport (ORD), Illinois, USA to Appleton International Airport (ATW), Wisconsin, USA
Date of Incident: 27 April 2025
Total Occupants: Not specified (CRJ-700 seating typically around 70 passengers)
Weather Conditions: No significant weather anomalies reported during departure or arrival phases
Introduction
On 27 April 2025, SkyWest Airlines flight UA-4748 operating on behalf of United Airlines experienced a bird strike enroute during its short sector from Chicago O’Hare to Appleton, Wisconsin. While no anomalies were reported during the flight itself, a post-flight inspection at Appleton identified a dent on the right-hand wing, attributed to the impact with a bird.
The incident was officially classified by the Federal Aviation Administration (FAA) as a wildlife strike, requiring mandatory reporting and technical investigation under current aviation safety protocols.
Sequence of Events
Flight UA-4748 operated under standard conditions:
Departure was from Chicago O’Hare’s runway 09C, a primary eastbound departure runway. The aircraft climbed normally to a cruise altitude of 16,000 feet, reflecting a typical altitude for the short domestic sector. The flight continued uneventfully towards Appleton, where it conducted a routine approach and landed on runway 03 approximately 30 minutes after departure.
There were no in-flight advisories from the crew regarding bird strikes, engine anomalies, or airframe vibrations that would suggest immediate operational concerns.
Upon post-landing inspection:
Maintenance personnel detected a dent on the aircraft’s right-hand wing. Subsequent assessment attributed the damage to a bird strike occurring during the flight phase. The specific phase of flight during which the impact occurred remains undetermined, although early post-departure (climb out) remains a strong possibility given typical bird activity patterns.
The aircraft was taken out of service pending detailed inspection and repair.
Crew & Communication
Throughout the flight:
No irregularities were reported by the flight crew either to Air Traffic Control (ATC) or internally through airline operations channels. There was no declaration of emergency or urgency (e.g., no Pan Pan or Mayday calls). Crew communications were routine, with standard check-in and approach calls logged with ATC.
This suggests that the bird strike impact was not perceptible to the flight crew during flight, a not-uncommon occurrence when strikes affect non-critical external structures rather than engines or windshield areas.
Aircraft Systems & Technical Analysis
The Bombardier CRJ-700 features a high-aspect ratio wing with winglets designed for aerodynamic efficiency.
Key observations from technical analysis include:
Bird strikes impacting wing surfaces can cause structural dents, skin punctures, or internal rib or spar deformation depending on bird size, speed, and impact location. Given no pressurisation, fuel system, or control surface anomalies were reported, it is likely the bird strike impacted a non-critical upper surface of the right wing. However, any dent—even minor—requires thorough inspection to rule out underlying fatigue risks, delamination, or hidden cracks that could propagate under aerodynamic loads.
The CRJ-700’s structural integrity protocols demand Non-Destructive Testing (NDT) methods such as:
Ultrasonic thickness checks Visual inspection under special lighting Dye penetrant testing if surface cracks are suspected
If any spar or load-bearing element was affected, structural reinforcement or panel replacement would be mandated before return to service.
Passenger Experience & Cabin Conditions
Given that no in-flight event was reported by the crew:
Passengers likely experienced a completely normal flight. No cabin disturbances, unusual noises, or vibrations were reported. No emergency procedures (such as brace position advisories or emergency landings) were initiated.
Passengers disembarked normally after arrival into Appleton.
Emergency Response & Aftermath
Since the event was only discovered during the post-flight inspection:
No emergency response or fire/rescue activation was triggered. Airport operations were unaffected. The aircraft was immediately placed out of service to prevent further operation until full inspections could be completed.
As of approximately 15.5 hours post-landing, the aircraft remains grounded at Appleton pending the outcome of detailed damage assessments and repair planning.
Given United and SkyWest’s operational protocols, the aircraft would not be cleared for any further movement until certified airworthiness is restored.
Investigation Status
The FAA confirmed the event via its preliminary wildlife strike reporting systems, listing:
Bird Strike on right-hand wing Damage description: dent to structural panel (extent of internal damage still under assessment) Location: Appleton International Airport, Wisconsin
No specific bird species identification was reported at this stage. Airports and airline maintenance typically conduct biological residue analysis (“snarge analysis”) to determine bird species, which assists with wildlife management efforts at airports.
SkyWest Airlines and United Airlines maintenance teams, under FAA oversight, will determine whether repair by local MRO (Maintenance, Repair, and Overhaul) facilities at Appleton is feasible, or whether ferry flight authorisation will be required for transfer to a larger maintenance base.
Root Cause & Contributing Factors
Primary Cause:
Impact with avian wildlife during the flight phase, resulting in physical damage to the right-hand wing of the aircraft.
Contributing Factors:
Birds at higher altitudes during climbout or enroute segments, a common but unpredictable hazard in North American airspace. Lack of immediate visual detection or in-flight awareness of the impact, typical when strikes occur at wing extremities.
Safety Recommendations & Industry Impact
Wildlife strike incidents, even when minor in outcome, reinforce the importance of:
Thorough post-flight inspections, especially following sectors involving climbout over areas known for migratory bird activity. Enhanced wildlife management programs around departure and arrival corridors at major and regional airports. Pilot awareness campaigns reminding crews to report any suspected bird strike immediately, even if not visibly confirmed.
SkyWest and United will also evaluate whether enhanced on-ground bird radar systems or strike mitigation strategies might be advisable at key airports including Chicago O’Hare.
Conclusion
SkyWest Airlines flight UA-4748’s bird strike over Wisconsin highlights the continued threat posed by avian wildlife to aviation safety. The structural damage to the aircraft’s right-hand wing, though discovered post-flight, underscores the necessity of rigorous aircraft inspections and proactive safety culture in routine flight operations.
Fortunately, in this instance, the event remained isolated to structural denting without injury to occupants or impact on the safe completion of the flight.
Disclaimer
This article is based on publicly available information and reports at the time of writing. While every effort has been made to ensure accuracy, we cannot guarantee the completeness of the information provided.
If you are the rightful owner of any referenced content or images and wish them to be removed, please contact takedown@cockpitking.com.
