Stephan, they will allow more separation for a light aircraft. But remember you are PIC. If you aren’t happy then you need to be clear on what you need. In my experience ATC at major airports are very careful about wake turbulence.
Stephan, if you get an EASA IR you will know wake separation rules by heart… you have to learn every combination of aircraft and about dependent parallel and independent parallel runways (760m, right?).
@achimha Ah! That’s the difference! Good to know :-)
must have moved approx 2-3km upwind initially, no?
Sorry. my arithmetic error: it would only be 40-50m, which is much more plausible, and need not have affected the parked helicopters. Scary.
I too would not have thought it would hang around for 30 seconds, so this is a learning point for me too.
Also I am sure I have seen (and flown through, uneventfully) cases of much closer proximity (in time) although usually it would have been against helis like Robinsons or maybe an MD500 and those are much lighter that the subject one.
The FAA’s AIM has pretty reasonable-sounding advice on a lot of this:
No way! You touch down BEFORE the rotation point of the preceding a/c! Otherwise you do exactly what this hapless Cirrus pilot did – fly straight into the vortices.
Yes, of course, if the preceding aircraft is taking off and you are landing! But that was not the case here. The helicopter and the Cirrus were both landing, right? At least the incident report mentioned the helicopter being ahead of the Cirrus in the traffic circuit.
So if the Cirrus was above the glidepath of the helicopter all the time, what happened?
Either the Cirrus pilot landed long or the helicopter made a steeper final than the Cirrus so that the Cirrus was, in fact, not above the helicopter’s path, or it was vortices from the air taxi. Or are we talking about two different helicopters.
Unfortunately neither PPL or IR training for fixed wing make much mention (if any) of helicopter vortex avoidance — only avoidance of vortices from other fixed wing aircraft. What jmuelmen writes above is what I’ve been taught too. But “Stay away from helicopters” is not much of a help if there is mixed fixed/rotary wing traffic.
That’s why I’m asking. Do vortices from helicopters behave in a different way from fixed wing vortices?
I’m supposed to touch down before the airliner but that might be difficult to achieve in bad weather. Will ATC provide enough time separation? I feel my wellbeing will be in the ATCOs hand – no?
Nope. Your wellbeing as a pilot is always in your hand.
Wings produce vortices if they produce lift, therefore:
If landing a light a/c behind an airliner, you fly above the glidepath of the preceding a/c. Pretty easy, just fly on three whites instead of two on the PAPI. You want to land after the landing point of the airliner.
Upon take-off, as DAR says. I you have a crosswind, rotate before the preceding traffic and fly your climb upwind. If the wind is straight down the rwy, then wait, as you may well climb straight into the vortices. Not a place you want to be in a light a/c. Also, you will never outclimb a jet, so the theoretical option of flying above the climb path of the preceding a/c isn’t an option, unless you fly a fighter.
But that was not the case here.
The way I understand it and also looking at the video, I think the helo was taking off.
The way I understand it and also looking at the video, I think the helo was taking off.
Well, the report said:
The student pilot stated that he entered the traffic pattern at FNL for a full stop landing on Runway 33. He observed a Sikorsky UH-60 helicopter on downwind and delayed his turn to base until the helicopter was on final, abeam his position. While on final, the student pilot adjusted his aim point to land long, as he was concerned with wake turbulence and wanted to land beyond the helicopter’s touchdown point. Just prior to landing, he encountered turbulent air and attempted to go around. The airplane subsequently impacted terrain and cartwheeled, which resulted in damage to the fuselage and wings.
No mention of that or any other helicopter taking off. I watched the video, too. Air taxi? The helicopter doesn’t appear to be climbing or accelerating.
When the video starts It looks like it is accelerating at low level to a safe climb-out speed, which is normal.
We cannot see whether it previously transitioned to a hover (lots of vortices, all around one spot on a low-wind day), or just went around.
