Aviation Data

There is the company/site/app called FlightAware that provides real-time and historical flight tracking data (flight paths, statuses, cancellations, delays and predictive analytics). It is popular among both aviation enthusiasts and travellers.

 

Ben Burwell wrote this piece on the eternal problem engineers have to deal with:

“While we as engineers might hope for aviation data to be clean and well-standardized, the real world is messy.”

All kinds of assumptions about standardized data types and schemas (formats) turn out to be false, making the development of FlightAware very challenging. He lists examples of invalid assumptions from multiple categories, some unsurprising, some downright weird. Click on the hyperlinks below for examples.

 

Flights. Flights depart from a gate. Flights leave their gate only once. Flights take off and land at airports. Flights are never longer than a few days. Flight numbers consist of an airline’s code plus some numbers, like UAL1234. Flights don’t have multiple flight numbers. The same flight number isn’t used by different flights during a day. Or even if that were possible, they wouldn’t depart within minutes of each other.

 

Airports. Airports don’t move! A runway is used by one airport only. They don’t have multiple IATA codes.

 

Airlines. Two airlines don’t share the same IATA code.

 

Navigation. There is one definition of altitude. Service providers won’t say a flight has departed when it hasn’t. If they say a flight is cancelled, it really is cancelled. Radars with overlapping coverage agree on what they see. A diverted plane can’t be re-diverted again.

 

Transponders. GPS messages in transponder messages is correct (with some margin for error). The message includes the flight identifier. The message includes an identifier of the aircraft (plane, helicopter). Identifier field cannot be empty. Transponders never break nor their cables get chewed by rats.

 

To paraphrase Shakespeare:

“There are more things in heaven and earth, Horatio,

Than are dreamt of in your philosophy software assumptions.”

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