Royal Charter (ship) by some passengers, though not confirmed, that the master, Captain Thomas Taylor, was advised to put into Holyhead harbour for shelter. He decided to continue on to Liverpool however. Off Point Lynas the "Royal Charter" tried to pick up the Liverpool pilot, but the wind had now risen to Storm force 10 on the Beaufort scale and the rapidly rising sea made this impossible. During the night of 25/26 October the wind rose to Hurricane force 12 on the Beaufort Scale in what became known as the "Royal Charter gale". As the wind rose its direction changed from E to
Subsonic and transonic wind tunnel interactions occur (such as shock waves or boundary layer interaction) both Mach and Reynolds number are important and must be properly simulated. Large-scale facilities and/or pressurized or cryogenic wind tunnels are used. With a sonic throat, the flow can be accelerated or slowed down. This follows from the 1D area–velocity equation. If an acceleration to supersonic flow is required, a convergent-divergent nozzle is required. Otherwise: Conclusion: The Mach number is controlled by the expansion ratio formula_11 Subsonic and transonic wind tunnel Low-speed wind tunnels are used for operations at very low Mach number, with speeds in the test section up