Temp/Dew spread is significant when < ?
2 deg or less
1 deg or 0 deg can still be ok for local flying near Ocean airports (Victoria, Lhr)
Whereas, Dry air won’t get any weather except Gusty winds, look at spread map on foreflight.
Flight watch frequency usa?
122.0
First contact full Callsign
…then only last ‘3’ of my n-number “25Q”
Will give weather and forecasts
When visibility is less than 4miles start thinking?
If there is Precipitation…then vis will be even less at higher altitude.
Fly around Snow Showers, like you would the bottom of CB in the summer.
D=V*T (<3nm is time divert) D/V
3/current groundspeed *3600= Secs of vis required right now, Hit Stopwatch!
hrs/min/sec
What wind changes cause a DPS?
Loss of Headwind
Increase of a Tailwind
Both make a/c fall, Go max power!
An overall change of windspeed of greater than 6kts per 1000’ means?
Turbulence
What happens on clear, cool nights?
Ground cools faster than airmass; an inversion of temperature; expect some shear as you transition the area on climbout.
When is the aircraft no longer moving ‘with’ the air in the instantaneous sense?
When the wind changes faster than the aircraft’s mass can be accelerated or decelerated.
Which conditions provide the worst frontal windshears?
-5hrs prior to a Warm fronts passage at altitudes below 5000’
-Assumes temp change >5deg
-Front speed 30kts or more
-More overall violent wx with Cold Fronts
What do ‘sharp’ edges on clouds indicate?
Moderate or Severe Turbulence
Which side of CB’s has windshear?
All sides!
Gust Front ahead
Downdraft underneath
What is the safe distance to remain from a CB?
15nm
Can’t out climb
Harder to deviate 100nm off course
Can barely outrun it
Any encounters on ground or air will have severe consequences…not like an airliner!
What do Surface winds of 30kts imply?
LLWS
Unable to Taxi safely
Divert or Hold winds decrease at Sunset
What is Virga? Not to fly under it, or through it, under a Tcu..
Precip that doesn’t hit the ground…a very bad sign, it is a visual indicator of potentially violent and often invisible vertical wind shear!
What ‘minimum G/S’ should I be looking for an approach in variable wind conditions?
30kts in variable winds
20kts if in steady stable winds
How to react to windshear?
Set RFC early
Add Full power
let the nose fall… don’t try to maintain alt
[Trading Alt for Ias]
Set F3
Set PA 12 deg (i.e. for a 3Pt)
Then trim for 70kts climb
Stopwatch number seconds of vis I have… then use what ‘formula’ ?
Sec/(3600 * gs) = vis in NM
You’re getting close to trouble when <XX sec vis ahead!
<80 sec
if currently Flying at a Fast GS then maybe 3nm vis, but if slow then only 1.5nm vis!
Time to Land Asap, anywhere I can.
Which way is a veering wind going?
Clockwise
To the right on Compass Rose
Numbers increasing.
What is weight of avgas per US Gallon?
6 pounds
Usually 100 octane
Indication of frontal passage?
90 to 180deg wind change clockwise
Temp change >2deg
Psi drops, the Psi rises
