Flight data Flashcards
1
Q
How is flight data recorded?
A
- FDR flight data recorder -> many different types(old models still in use)
- CVR cockpit voice recorder
2
Q
What devices are used on board?
A
- measurement
- aquisition/processing (FDIU Flight data interface unit)
- recording (FDR, CVR, QAR quick accsess recorder)
- output (wireless, disk, pc card)
3
Q
What are some requirements for CVRs / FDRs?
A
FDR: - must be on board to record parameters + voice related to crash - data is continiously overwritten - located in the rear of the aircraft - painted yellow/orange - at least for the last 25h ICAO: flight path, speed altitude, engine power.. CVR: - records pilot microphones+earphones - records all ATC+intercom conversations - Records background using area mic - at leasr the last 30 min, since 2016 2h
4
Q
How is data structured in ARINC717?
A
- records in 64/128/256/1024/2048 words per second
- each word is 12bits (stored in 16bit blocks)
- each second is calles a subframe-> 4subframes= 1frame->16 frames=1 superframe
- 4 different subframes, identified by unique sync words
5
Q
How are different sampling rates realized? ARINC717
A
depends in Bit number: 64/128..
??
6
Q
How to read a parameter in ARINC717 given word & subframe position?
A
- sync words identifies subframe 1, 2, 3, 4
- unique decoding table which shows the position of the parameters in the subframes
7
Q
What other sources of information are there?
A
- ADS-B (automatic dependend surveillance broadcast)
- NOTAM, METAR, SIGMET
- terrain data
- airspace configuration
- radar tracks
- flight plan
8
Q
Why is QAR data Big Data?
A
- file size: 2-200MB, 39 Mio flight 2019
- many different informationfrom all stakeholders
Big Data - volume (Data at Rest): terabytes-exabytes of data
- velocity (Data in Motion): streaming data, milliseconds to seconds to respond
- variety (Data in many forms): un/structured, text, multimedia
- veracity (Data in Doubt): uncertainties due to inconsistencies, incomplet, latency, deception, model approximation
9
Q
How to work with such data on a large scale?
A
- setup depends on the volume/costs/…
- online requires de-identification