Why didn't I hit Wake Turbulence

Jaybird180

Jaybird180

Final Approach
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Jaybird180
Not that I wanted to...

This past weekend, I operated to/from Atlanta Hartsfield. I landed at night and traffic was relatively light. They used the outer runways for landings and inner runways for departures.

wunderground.com historical data says the winds were calm when we departed Rwy08L Monday morning. I didn't watch my clock, but I was cognizant of the Wake Turbulence issue and in preparation for the flight, I watched the FAA video on youtube, as it's been awhile since I've operated at a Class B airport.

My instructions were hold short 8L #5 for takeoff. As I was doing other things, waiting....I spied the 2nd jet takeoff. No idea when #3 and #4 left, but I think they bumped me up and I got the call to "line up and wait", so I did. I watched the jet in front takeoff and remain on runway heading per NOTAM. My clearance was "remain runway heading until departure end, turn 020, remain at or below 2,500, expect 7,500 (requested altitude) 10 minutes after departure, contact Atlanta Departure xxx.xx, cleared for takeoff.

In my pre-takeoff briefing, I'd briefed my wife that we should expect to turn about midway and I had already visually cleared the area prior to boarding the aircraft. Needless to say, I was very concerned about wake avoidance. However, the experience was sans drama of any sort. There was absolutely NO WAKE. I was expecting to pass through it. Maybe I was in a time warp where space/time changed and I did wait sufficient time for the wake to dissipate. I did note that there was a delay between #1 and #2's departure. I won't know for sure how much time elapsed after the jet taking off before I pushed the throttle until I review the video, which I'll start editing in about a day or two.

Are there other ways the wake could have dissipated?

BTW- I reviewed these 2 threads prior to posting
http://www.pilotsofamerica.com/forum/showthread.php?t=72239
http://www.pilotsofamerica.com/forum/showthread.php?t=72262&highlight=wake+turbulence
 
The wakes can be sometimes hard to find. First off while you climb rate isn't anywhere near what these jets are, your takeoff roll is shorter and your climb angle is likely steeper. That and the fact that wakes settle.
 
My guess is that you were well above it while over the runway, then turned left to your 020 heading before you had the chance to wander into it. The big jets are going to outclimb you eventually, but it takes time to rotate and pitch into our climb attitude.
 
Unless the controller gave you a wake turbulence warning, he probably had you wait the appropriate time for it to dissepate.
 
If wake is a possibility, ask the controller for immediate turn to avoid the wake or wait the time for wake to dissipate. Another simple way during calm wind, fly runway heading as instructed BUT far right or far left of runway to avoid departing wake Or on the upwind side of runway from departing jet.

I have asked for early turn for wake turbulance, when I did not think I could avoid it, no problem, other times, I have been held for 2-minutes if I could not get the turn out, I requested.

Dont expect to feel it, avoid it!
 
ATC also has 2 & 3 minute holds for wake turbulence depending on the aircraft weight, intersection vs full runway departure etc. My guess is, you had so much time waiting that the wake was no factor. It probably settled well below your departure angle.
 
If you suspect wake turbulence from a heavy is a possibility, hold. ATC usually does a good job of sequencing but I've had interesting rides from wake from planes as small as 1900s. I do not care to find out what 737 wake turbulence would do to my 207. Be very very careful as I feel wake turbulence is one of the most hazardous things you can encounter in a small airplane, and it is often overlooked. As mentioned previously, a very early turn (as in as soon as you are clear of immediate obstacles in the departure direction) or 2 minutes from when the jet took off. Calm wind days are the most dangerous.
 
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