The clock rule taught for crosswind reads high, most of all at sixty degrees
The crosswind on a runway is the wind speed times the sine of the angle between wind and runway, and flight training tea...
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Jet lag by direction, worked through on routes out of Singapore and Hong Kong
Flying east asks the body clock to run earlier and flying west asks it to run later, and early estimates from real fligh...
Shortcut WBGT formulas land on both sides of Singapore's measured heat stress
Singapore's official heat stress readings blend three thermometers, one of them in the sun. Checked against 30 MSS stati...
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Humidity adds close to 400 feet to density altitude at Changi
Water vapour is lighter than dry air, so humid air raises density altitude even at a sea-level airport. At Changi's Apri...
The same wind speed can mean twice the pressure, depending on its averaging time
Wind pressure follows the square of the speed, so whether a figure is a 3-second gust or a 10-minute mean can more than...
Thunder covers a kilometre in under three seconds in Singapore air
Dividing the seconds between a lightning flash and its thunder by three gives kilometres, but in Singapore's air sound c...
NParks allows about twice the time Naismith's rule gives on Singapore trails
Naismith's 1892 rule allows an hour for every three miles plus an hour for every 2,000 feet of climb, and the day he sai...
Why stopping distance charts disagree at the same speed
At 90 km/h, Singapore's driving handbook says 95 metres, Britain's table gives 73 at a slightly higher speed, and US roa...
One sky, three verdicts: why Singapore says unhealthy and Malaysia says moderate
The same 70 micrograms of fine particulate reads 116 on Singapore's PSI, 96 on Malaysia's API and 161 on the US AQI. Alm...
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