CharlieTango
Line Up and Wait
- Joined
- Oct 14, 2013
- Messages
- 878
- Location
- Mammoth Lakes, California
- Display Name
Display name:
CharlieTango
Be prepared when coming here on windy days, avoid the first 3,000' of runway 27.
Silly question, I know, but what happened?!?!
What happens with the first 3000'. I see the A/FD says turbulence and windshear. Why doesn't that happen with the next 4000'? I have never landed there but have driven by the airport many times and it seems the terrains is basically the same all the way along the runway.
Thank you for the great description. I am based at KRNO and would need to find a really nice, calm day to take a trip to Mammoth... sounds like some crazy winds down there.
What a lame place to build a airport.
One of the most beautiful places to visit IMO. But I have a soft spot for the Eastern Sierra.
Ouch
Pranging the nose wheel, or a PIO is simply a result of bad training and technique IMO.
Sorry about your clubs plane.
Speaks volumesThe southerly crosswind is complex it comes mostly from Convict canyon (13,000'+ terrain) abeam midfield and is usually turbulent due to the 1,500' glacial moraines. The actual prevailing wind at altitude is generally SW so there is also a west wind coming from Mammoth Pass colliding with this south wind and creating mid-field shear.
In the first 3,000' there is high terrain on the north side. The south wind first hits the high moraine and become turbulent then crosses the runway in the 1st 3,000' and and hits 'Doe Ridge' the high terrain just across the runway and then rotors back laterally in 2 distinct northerly crosswinds.
There is also the termination of the Owens Valley sending an east wind that can collide mid field.
So in the 1st 3,000' of 27 you can encounter an East wind, 2 north wind rotors with opposing rotations, a turbulent south wind and a west wind.
We know to overfly the 1st 3,000' because that takes us to where the old runway used to end.
It appears that the runway was shifted eastward from its previous location, which then subjected it to this problem. Any idea why?
JKG
Only one slightly bent prop tip?
Are we sure this happened on the runway, rather than due to that crappy tie down job in high winds?
I'd expect that prop to look a lot worse -- and for all the tips to be damaged -- if he landed hard enough on the nosegear to collapse it. And the sideload should have taken out a wingtip.
Is there an STC on making it an RG?
The southerly crosswind is complex it comes mostly from Convict canyon (13,000'+ terrain) abeam midfield and is usually turbulent due to the 1,500' glacial moraines. The actual prevailing wind at altitude is generally SW so there is also a west wind coming from Mammoth Pass colliding with this south wind and creating mid-field shear.
In the first 3,000' there is high terrain on the north side. The south wind first hits the high moraine and become turbulent then crosses the runway in the 1st 3,000' and and hits 'Doe Ridge' the high terrain just across the runway and then rotors back laterally in 2 distinct northerly crosswinds.
There is also the termination of the Owens Valley sending an east wind that can collide mid field.
So in the 1st 3,000' of 27 you can encounter an East wind, 2 north wind rotors with opposing rotations, a turbulent south wind and a west wind.
We know to overfly the 1st 3,000' because that takes us to where the old runway used to end.
Ummmmit already is RG.
Now its a BRG "Bent Retractable Gear"
According to the line man this 182 landed on 27 with gusts to 50kts. The incident happened at Alpha 1, turning off the runway there would likely put the bulk of that 50kts on your tail.
Two lessons here,
1) Avoid the 1st 3,000' of 27 when southerly crosswinds exceed 15kts.
2) Request wing walkers before turning downwind to exit the runway.
If you follow basic taxi control rules, 'climb into, dive away', in high winds, you will have little problem. Tail draggers without a locking Tailwheel can have some issues that take some skill and throttle work, and occasionally a 270° turn, but I used to taxi in all sorts of hellacious winds in W-Texas and never needed a wing walker.
Its not just the wind velocity but all of the shear. This 182 exited where there is high terrain on both sides and resulting winds and rotors from 5 directions at once.
The AFD says: Arpt lctd in mountainous terrain with ocnl strong winds and turbulence... With southerly crosswinds in excess of 15 kts, exp turbulence and possible windshear along first 3000´ of Rwy 27.
Later that day I was unable to walk in front of my hangar in the 80mph gusts. The NWS had issued warnings that day that walking would be impossible.
This aint Texas Henning, you can tell buy the 13,000' terrain within 2 miles of the field.
Oh, I understand about avoiding the the first 3000' due to shear, Big Bear is similar, actually many airports have similar issues from surrounding terrain and even structures.
My question was one of needing wing walkers to safely exit the runway.