Happy New Year from the Met Office Aviation team!
The festive period is often a busy time of year for air transport as many of us visit friends and family. It may also be a time of year when winter weather could cause disruption. This blog post looks at the cost that weather has on the industry and what we are doing to help.
This is a very broad subject – enough to write a book on – but it perhaps could be looked at in two ways:
- Costs in ‘non-disruptive’ weather
- Costs due to ‘disruptive’ weather
Of course also important is what we are trying to do to help reduce these costs.
What do we mean by ‘non-disruptive’ weather?
I would suggest that this is any weather that does not create a significant deviation from the schedules for airline or airport planning. These costs could therefore be looked at as achieving greater efficiencies in day to day operations.
Perhaps the largest impact is the relative head and tailwind component for an aircraft in-flight. An airline will typically plan its schedule on the 65th percentile of flights times (i.e. a reasonable assumption of the most likely flight time). So, a stronger than ‘normal’ headwind will effectively increase the flight time and a stronger than ‘normal’ tailwind will speed the aircraft up so decrease the flight time. Of course these variances in wind speed and direction can be counteracted by increasing or decreasing the thrust applied to the engines. But, this also has an impact on fuel use and therefore cost.
So, what does the Met Office do to try and help minimise these costs and enable improved efficiency? Our global model is continuously developed and upgraded to maintain its leading position in terms of forecast accuracy which enables accurate flight planning. In addition, we are working with partners such as Avtech to provide in-flight updates of wind and temperature in high resolution (or high detail) to enable increased efficiency in flight both en-route and in the descent phase of flight.
… and ‘disruptive’ weather?
Moving on to look at costs due to disruptive weather, this could be anything which causes a departure from an airline or airport’s normal schedule.
At airports, this includes aspects of weather which impact on the safe and timely arrival and departure of aircraft, including: low visibility, low cloud, snow and ice, thunderstorms at the airport and nearby, plus strong winds. In airspace (during the en-route phase of the flight), this can include thunderstorms, turbulence, very strong winds and volcanic ash.
The weather often sets off a complex chain of events which ultimately can create significant cost and disruption to the travelling public. For example, if low visibility or fog forms unexpectedly at an airport, less aircraft will be able to land per hour. This means that aircraft already in-flight may have to circle in the air waiting to land, burning extra fuel. If this continues for too long, the aircraft may not have enough fuel and the crew may therefore decide to divert elsewhere to wait and re-fuel. If this happens, there is extra fuel required for the additional landing and takeoff to get back to the intended airport. Plus the aircraft and crew may also not then be available for the next flight, creating further complexities. Then if the delay exceeds 3 hours, passengers may be able to claim for the delay under EU compensation laws. So, very quickly, an apparently small change in the weather can have a large impact on an airline and airport’s operation, leading to significant costs (possibly millions of pounds).
All of these weather phenomena are predictable. However, this predictability varies from event to event and is also dependent on location. We work with airports and airlines closely to help determine what predictability is realistic for these events and therefore what planning and contingencies can be enabled. Depending on the airport, we will also provide very detailed forecasts for each weather type, focused on the key thresholds and relevant lead times.
We will be writing more blogs on all of these weather types and the impacts, so watch this space!
Jon Dutton – Aviation Business Manager.