Only a matter of time.
https://www.dailymail.co.uk/sport/sport ... hheld.html
AFSAG wrote:Just playing with some numbers and an online pitot/static simulator
Start at 5000ft and 160 knots, OAT 0c QNH/QNE 1013
Then block the static vent due ice
provided neither altitude nor speed change there are no effects
But, descend say 500 ft
Now altimeter shows 5000, but IAS has increased to 180
So slow down to 130 in order to make the IAS 160
Request descent to say 3500
Now indicated altitude is still 5000 but IAS is now 210
So slow down to get IAS right- reduce to 60 and IAS still showing 180
To get IAS to be 160 you need to reduce TAS to less than 0 when the PA46 stalls at ? 60
This is with a complete blockage- partial would be more insidious
We don’t know if the aircraft was hand or autopilot flown- if autopilot even easier to fly into the stall without even realising it
Presume ROV will have looked for alternate static lever position- which would be the solution to the above, but a pilot with degraded performance due to human factors issues around the flight might miss it,
Pitch + power=performance also needs good mental capacity at a time of high stress and startle effect
How easy do static vents ice up in a PA46?
…if there's icing in cruise, keep the speed above 140 kts.
G-BLEW wrote:A PA46 observation passed on to me a few years ago by a Piper production test pilot.…if there's icing in cruise, keep the speed above 140 kts.
I presume the increased AoA below 140 kts allows ice to form beyond the reach of the boots.
That said, although icing is mentioned frequently in relation to this accident, I personally haven't seen an icing forecast for the time/area.
Uptimist wrote:Just curious (I have no IR): would it be usual to cross check GPS supplied altitude and ground speed (if available) against that reported by mechanical altimeter/ASI in icing conditions, or would you only think to do that once you were aware of a possible problem (e.g. blocked vent), by which time perhaps it would be too late?
Flintstone wrote: power plus attitude equals performance…Which is all well and good I suppose when your wing isn’t covered in ice.