Blog
FDC
Monitoring Small Aircraft 2
on May 18, 2017

Background In January 2015 I wrote a short blog entitled “Monitoring Small Aircraft”. It described how we can monitor relatively small aircraft when they are equipped with modern digital avionics. Specifically (and please don’t interpret this as advertising) the Garmin G1000 system, which includes a data card facility for recording flight data. The original […]

FDC
Following the Taxiways
on April 21, 2017

In this blog I will explain how we compute the ground track for visualisations and why this is undergoing a process of revision. What the User Sees When we process flight data we often show the flight on a chart or, most commonly these days, on Google Earth. It is easy to see where the […]

FDC
What is the Groundspeed?
on March 15, 2017

Recently a customer asked whether the groundspeed recorded by the flight data recorder was right. They had (allegedly) exceeded a taxi speed limit by a large margin and suggested, very politely, that we had got this wrong. This prompted me to do some checks and as the results were interesting I thought I would […]

FDC
Why Two Vertical Speeds?
on February 20, 2017

Following on from last week’s blog about rates of change, it occurred to me that I should have mentioned the second computed vertical speed and explained why we have two measurements for the same thing. After all, surely the vertical speed is exactly that. Why have “Vertical Speed” and also “Vertical Speed Inertial”? Quick Look […]

FDC
Rates of Change
on February 13, 2017

One of our analysts asked if I had written a blog about how we calculate vertical speed, and I said “of course I did, ages ago”. There followed a 15-minute hunt for the subject and eventually I had to admit that it was missing, so here goes with a quick blog to plug a gap […]

FDC
Where an Aircraft Lands – Part 3
on February 6, 2017

We found out which airfield the aircraft landed at, and now need to pick the right runway. Selecting the Runway From basic flight phase analysis we know when the landing roll took place. Using the recorded heading we take the median heading during the landing roll as the direction of the runway. Note that we […]

FDC
Where an Aircraft Lands – Part 2
on January 30, 2017

My last post talked about some of the problems with finding out exactly where an aircraft lands. Now I will start to look at how the system works in practice. Pick an Airfield I will skip over the detail of how to identify the point of landing (this was covered in an earlier blog), so […]

FDC
Where an Aircraft Lands
on January 13, 2017

Some time ago I was asked to write about how the POLARIS software decides where an aircraft lands. At the time we knew of some limitations of the system and were planning to revise that part of the analysis, so it seemed sensible to hold on until that revision had been completed. These limitations have […]

FDS
Why Smoothing?
on January 5, 2017

Occasionally I have been asked why parameters in the POLARIS software are described as “Smoothed”. You will find Smoothed versions of Latitude and Longitude, Altitude STD, Gross Weight and soon to be Pitch and Roll (we are adding these to provide cosmetic improvements for visualisation displays). It’s a bit of a history lesson, so makes […]

FDC
Keeping up to date
on December 21, 2016

It is important in flight safety, as with most other things in life, to keep up with changes in regulations and procedures, and to keep up with industry best practice. It occurred to me that one safety lesson which I was told many years ago by my old friend and mentor, Capt Simon Searle, should […]