© Copyright 2026 All Rights Reserved
“The air is beautiful, yet utterly unforgiving.”
The National Transportation Safety Board (NTSB) determined that the July 27, 2013, crash of a Piper PA-28R-200 aircraft in Lake Michigan was caused by an in-flight breakup after encountering wake turbulence.
The encounter happened less than a minute after the Piper Arrow’s flight path (northerly heading) crossed the final approach course (westerly heading) of an MD-80 commercial airliner inbound to the General Mitchell International Airport (KMKE), Milwaukee, Wisconsin.
The NTSB’s Final Report indicates that the Arrow crossed the flight path of the MD-80 at 1,800 feet (msl) about 39 seconds (1.4 miles) after the MD-80 had passed the same location at the same altitude. The air traffic controller’s plan had the Arrow pass behind the descending aircraft but failed to issue a wake turbulence advisory.
Per the NTSB, although wake turbulence is primarily the pilot’s responsibility, the Federal Aviation Administration Air Traffic Control Handbook (FAA Order JO 7110.65) does require controllers to provide pilots with a wake turbulence advisory if, in the controller’s opinion, wake turbulence may adversely affect the aircraft. In this case, the NTSB determined the approach controller should have been cognizant of the potential hazard and issued a wake turbulence advisory to the pilot.
Ultimate responsibility for avoiding wake turbulence remains with the pilot, particularly when operating VFR or accepting visual separation clearances.
The Arrow likely encountered the vortex, resulting in a catastrophic in-flight breakup. Two fatalities.
This is the seventh article in my series on The Basics of Flying. As I explained in the initial piece posted online in Midwest Flyer Monthly (January 2026), “[t]his should not result in new information being imparted to pilots; instead, it should serve as a refresher course to remind pilots of information they once knew, and can recall again, if prompted.”
Wake turbulence remains one of the most underestimated hazards in general aviation (GA). Though invisible, the vortices trailing from an aircraft’s wingtips can impose forces strong enough to overpower the control authority of a light airplane in seconds. While many pilots associate wake turbulence with heavy jets, accident data shows that helicopters, business jets, and even other GA aircraft are frequent contributors to wake‑related incidents as well.
This article explores how wake turbulence forms, why it is dangerous, and how GA pilots can avoid becoming its next victim.
What Wake Turbulence Is
Wake turbulence is a natural byproduct of lift. As air flows from the high‑pressure area beneath the wing to the low‑pressure area above it, two counter‑rotating vortices form: the left vortex rotates clockwise, and the right vortex rotates counterclockwise.
These vortices behave like horizontal tornadoes, trailing behind the aircraft and sinking as they move.
Vortices are strongest when an aircraft is heavy, clean (flaps and gear up), and slow. This combination creates the most hazardous wake conditions for GA aircraft.
As William K. Kershner (1929 – 2007), distinguished flight instructor and author, in his discussion of wake turbulence, wrote in The Student Pilot’s Flight Manual, “Always be leery of taking off or landing close behind another plane. The bigger the plane, the more cautious you should be.”
Also, be aware that a wing generates wingtip vortices only when it is producing lift. A taxiing aircraft is not a threat to small aircraft to produce wake turbulence. However, some taxiing aircraft may still pose a serious threat because of jet engine blast. To avoid jet engine blast damaging or overturning a small airplane, it is prudent to remain several hundred feet behind a jet with its engines operating.
Why Wake Turbulence Is Dangerous for GA Aircraft
Induced Roll
A strong vortex can exceed the roll‑control authority of a light aircraft. Even full opposite aileron may not be enough to counter the roll.
Structural Stress
Severe encounters can impose loads that risk structural damage, though loss of control is the more common outcome.
Accident Data
NTSB investigations show dozens of GA accidents linked to wake turbulence over the past two decades. Notably, helicopters were responsible for more wake‑related GA accidents than any other non‑airliner category. See, for example, the NTSB Preliminary Report on the recent fatal crash involving a Pennsylvania State Police helicopter and a Cessna 150 at the Carlisle, PA airport (N94) on August 19, 2026. The available video suggests wake turbulence was a factor in the accident. In addition, business jets can also generate wake strong enough to upset trailing light aircraft.
How Wake Vortices Move
Wake vortices do not remain stationary. Vortices may stay in the air for several minutes. Their behavior depends on atmospheric conditions and proximity to the ground.
Sinking
In calm air, vortices typically sink 300–500 feet per minute until they reach the ground.
Prior to the NTSB Report referenced at the top of this article, I believed, as did most pilots I know, that so long as your aircraft crossed the path of a heavier aircraft at or above the altitude of the heavier aircraft, you would be safe, as the vortices generally tend to sink and dissipate over time.
As indicated, vortices behavior “depends on atmospheric conditions and proximity to the ground.” Clearly, in the Piper Arrow’s case, 39 seconds later and crossing at the same altitude was not a sufficiently safe margin. Instead, it was lethal.
Lateral Drift
Light crosswinds can push the upwind vortex across the runway. The downwind vortex may remain nearly stationary, creating a trap for following aircraft.
Ground Effect
As vortices descend, they interact with the surface and begin to move outward at 2–3 knots, sometimes lingering in the runway environment longer than expected.
Helicopter Wake: A Special Hazard
Helicopters generate wake turbulence that can rival or exceed that of much larger fixed‑wing aircraft. Hovering helicopters produce intense downwash. Forward flight creates chaotic, unpredictable vortices.
Light aircraft taking off or landing behind helicopters are at particular risk.
GA pilots often underestimate helicopter wake, making it a recurring factor in incidents and accidents.
High‑Risk Operational Scenarios
Takeoff Behind a Larger Aircraft
A light aircraft rotating too late or climbing too slowly may fly directly into the preceding aircraft’s wake. Mitigation: rotate before the preceding aircraft’s rotation point and climb above its flight path. If there is a crosswind, and if the runway is wide enough, take off on the upwind side of the runway, not the centerline.
Landing Behind a Larger Aircraft
Vortices settle near the runway and can linger for minutes. Mitigation: stay above the preceding aircraft’s glide path and touch down beyond its touchdown point. If there is a crosswind, and if the runway is wide enough, land on the upwind side of the runway, not the centerline.
Intersection Takeoffs
A light aircraft departing from an intersection may enter wake from a larger aircraft that departed earlier. Mitigation: delay takeoff or request a wake turbulence delay. As pilot in command (PIC), you have the authority. Use it when circumstances require it to remain safe.
Intersecting or Parallel Runway Operations
Crosswinds can push vortices from one runway into the path of aircraft on another runway. Beware of simultaneous operations on intersecting or parallel runways.
Following Helicopters
Even small helicopters can generate dangerous wake. Mitigation: avoid flying below or behind a helicopter’s flight path. Best to allow overly generous spacing.
Recommended Distances
When a helicopter is hovering, light plane pilots should be aware of and adhere to the “The Three Rotor Diameters Rule” – At least three rotor lengths minimum from the helicopter.
When a helicopter is in forward flight, light plane pilots should allow a three nautical mile distance when trailing behind.
Allow at least two minutes for rotor vortices to dissipate after a helicopter has departed in forward flight.
Beware that larger helicopters produce more significant and dangerous wake turbulence.
Avoidance Strategies for GA Pilots
Visualize the Vortices
Pilots should mentally picture where vortices are likely to be, based on aircraft size, flight path, wind direction, and phase of flight. This is easier said than done. Nevertheless, make the effort. Use more than ample guesstimates of time, direction, and duration to pad your safety margin.
Wake turbulence may remain for several minutes, long after the aircraft that created it may have landed or flown out of sight. Only you, as PIC, have a direct and personal stake, i.e., your life, in recognizing and avoiding the risk – not the pilot whose aircraft created the wake, and not ATC who may or may not issue a warning – only you.
Use Proper Spacing
ATC provides separation minima, but VFR pilots must self‑manage spacing. When a pilot accepts a clearance to visually follow a preceding aircraft, the pilot accepts full responsibility for their own separation and wake turbulence avoidance.
Fly Above, Not Below
Vortices sink – use altitude to your advantage.
Land Beyond, Takeoff Before
These simple rules prevent many encounters. But as PIC, you need to anticipate, think, and act.
Be Cautious in Light Winds
Light crosswinds can trap vortices over the runway causing them to linger in the vicinity of the runway or causing them to remain near a flight path in the air.
Respect Helicopter Wake
Give helicopters the same spacing you would give a large jet. If you have ever witnessed a Sikorski UH-60 Black Hawk helicopter (max gross weight 22,000 lbs.) land or takeoff, you have seen the wide perimeter ground crews set up, and you have likely felt the rotor downwash and wake well outside of that perimeter.
Why Wake Turbulence Still Surprises Pilots
Despite training and published guidance, wake turbulence accidents persist due to self-confidence, i.e., “It is not a problem because it has not been a problem,” misjudged spacing, self-induced pressure to maintain traffic flow, and lack of awareness of vortex behavior.
Key Takeaways
Accept the invisibility: You cannot see the danger, so you must mentally visualize it on every flight.
Practice active awareness: Wake turbulence requires anticipation, not reaction.
Respect heavy aircraft and helicopters: A large jet (heavy, clean, and slow) or helicopter generate vortices that can violently flip a small airplane upside down – on the runway or in the air.
Avoid complacency: Wake turbulence can linger in calm air, meaning the danger remains long after a heavy aircraft or helicopter has passed.
Speak up always: Never hesitate to ask ATC for a delay if you think a wake hazard is present. If in doubt, be assertive – give yourself a chance. Delay your takeoff on the ground or modify your flight path and altitude in the air.
Wake turbulence is invisible, powerful, and callously indifferent to logged hours, experience, pilot ratings, or aircraft type. Every aircraft and helicopter generates wake, and light aircraft are especially vulnerable. By understanding how vortices form, how they move, and how to avoid them, GA pilots can dramatically reduce their risk.
Note: I operated out of Batten International Airport (KRAC) for many years. When arriving from or departing to the north, I often flew along the shore of Lake Michigan, receiving flight following advisories from Milwaukee (KMKE) ATC. On one trip, flying south to KRAC past Milwaukee with a non-pilot friend, ATC advised of landing traffic, a B737, crossing east to west at my twelve o’clock. My friend was impressed, as the B737 crossed just a few miles in front of us at our altitude. After the Piper Arrow accident in 2013, my recognition of what runways were active at KMKE, and my awareness of, and respect for, wake turbulence, increased significantly.
© Copyright 2026 Dean Zakos All Rights Reserved
DISCLAIMER: Mr. Zakos’s articles should not be used for flight training or misconstrued as instructional material. The articles represent the author’s personal opinions. Readers are urged to always consult with a Certified Flight Instructor and other sources about anything discussed herein.
