Bicester Aviation Services

IGC Approved Secure Flight Recorders - Part 4

In this part, I am going to evaluate one of the first flight recorders on the market, the Peschges VP8 and then go on to describe one of the first combined variometer and flight recorder systems, the Filser LX5000/DX50.

This Page - SFR 4 - Peschges VP8 & Filser LX5000IGC/DX50IGC

The Peschges VP8

The Peschges VP8 was an early entry into the realm of approved flight recorders. It is a rectangular box, the size of a 35mm turn point camera, with a small LCD on one end, a single push button, and an integral GPS antenna on the top. It is designed to be mounted on the canopy rail in place of a camera and where the pilot can view the LCD screen. It has a 6 pin miniature connector on the far end which couples with the glider's 12 volt power supply, accepts the connection of the engine run detector and, when transferring data, is supplied with lead that connects this port to a power supply and PC.

The unit has a fixed logging rate of 6 seconds. It can store up to 255 waypoints and a task using these waypoints can be declared. However, the entry and manipulation of the way points can only be done by connecting to a PC using the comprehensive software programme supplied. The push button cycles through a series of screens that give basic navigational information and pressure altitude. The push button can also be used to active the pilot event marker (PEV).

The VP8 detects turbo engine operation by sensing the output voltage on pin 10 of the Ilec turbo control box as fitted to Schempp Hirth gliders. Pin 10 of the control box has a voltage level which is proportional to engine RPM. In order to activate this feature, pin 10 of the control box has to be connected to one of the input pins on the VP8. Furthermore, this electrical connection has to be sealed and correct operation verified by an Official Observer both before and after flight. Full details are in the FAI/IGC approval document.

While the VP8 is a robust, well engineered product, it is expensive when its features are compared with later products from other manufacturers. Furthermore the method of detecting engine operation is restrictive and labourious.

The Filser LX5000

The Filser LX5000 is very different from all the other IGC approved flight recorders. It is a combined GPS, variometer system, glide computer and IGC flight recorder all in one package. The unit is designed to fit in a 80mm (3 1/8") standard instrument cutout with a seperate LCD variometer in a 58mm (2 1/4") cutout. The variometer system is an extremely comprehensive unit, a full description of which is beyond the scope of this article. However, the integral IGC flight recorder will be described in detail.

The first noticeable difference with this unit is that it is plumbed both electrically and pneumatically into the glider. Therefore it is not practicable to remove the unit in order to transfer the flight data. Accordingly, a small 5 pin Binder plug is supplied which is mounted on the panel and a standard COM lead is connected to this plug so that the unit can be downloaded direct to a laptop. The flight recorder data can also be transferred to a Filser LX20, LX21 or Colibri and thence to a desktop PC.

The flight recorder is powered by the glider 12 volt supply and is automatically turned on when the vario is powered up. The unit will accept voltages from 9 to 36 volts with a total consumption (vario, GPS and recorder) of about 300 m/a. All the relevant sensors, such as the GPS and the altimeter, are common to both the vario system and flight recorder. A series of configuration pages are provided to set up the vario system and one of the pages enables the user to configure the flight recorder parameters. The default recording rate is 20 seconds but it can be changed as required. In addition to the normal recording rate, a faster recording rate can be selected when close to the TP and this normally defaults to 2 seconds. With a 10 second recording rate selected, the total memory capacity is 15 hours and when full, the memory 'rolls over', deleting the oldest flight records.

The unit can be pre-programmed with up to 5000 airfields and 600 user selected turn points. Up to 100 tasks can be stored in the unit and recalled as necessary. One of the tasks can be electronically declared for FAI badge/record purposes. The graphical page can be configured to show either the FAI photo sector or a cylinder, and the gliders entry into the TP zone can be seen graphically. Engine operation is recorded automatically by means of a built in microphone which produces a clear indication of engine running in the analysis programme. After flight, the flight recorder data has to either be transferred to a lap top PC or a Filser LX20, LX21 or Colibri flight recorder. It can then be taken to a desk top PC for analysis.

The LX5000 performs well as a flight recorder and is an ideal solution if the owner wants a combined unit that is using the same GPS information for both navigation and verification, an important factor in today's competition enviroment. On the debit side, it requires access to a lap top computer or another Filser recorder to transfer the flight data, and should the barographic element need to be calibrated, then the whole unit has to demounted from the glider and taken to a calibration chamber.

The Filser DX50FAI

A similar, but much cheaper, instrument, the Filser DX50 has many of the same features as the LX5000 and also incorporates an IGC approved flight recorder. However, the DX50 has no engine running recording capability, is a 'non standard' size, and has no co-processor which means that the graphics displays are slower to be drawn. On the plus side, the DX50 instrument can be easily removed from the glider facilitating the transfer of the flight recorder direct into the PC.