LED Flash & CalGnome


This blog contains all information about the LED-Flash and the CalGnome built and sold by How2Soar. More info here.

This part of the web site is still under construction.

When you encounter a button saying "Weiterlesen", you may push it to expand the article to complete size. I apologize for not having found a possibility to translate that button.

In the same sense : Button "weiter" means "proceed to next article", button "zurück" means "jump back to previous article".


Blitzer in einer ASG 29 Es

Product descriptions / installation manuals

These manuals and publications are updated at irregular intervals. Please make sure that you use to the most recent version.


Four types of flashes

Size of these flashes :

  • Mini-Flash for Duo, Arcus,ASH,25,ASK31
  • 90 * 60 mm
  • Standard Size
    • 155 * 60 mm
      (you may shorten the upper and lower flaps)
  • DG
    • 190 * 65 mm
      (you may shorten the upper and lower flaps)
  • Antares
    • 120 * 80 mm


    If you are about to order a "CalGnome", please read the manual in detail. There are order options which can only be understood in context of the paper (jumper in power source wiring / sense of logic of micro switches).

    BTW, If you plan to use an LX device as source of your Flarm data stream, please call me. Unfortunately, LX does not adher to the Flarm IGC plug pinout standard (RJ12 instead of RJ45). You might be in need of a special cable.


    Orders may be sent to my Consulting Office as a nonformal mail at Diese E-Mail-Adresse ist vor Spambots geschützt! Zur Anzeige muss JavaScript eingeschaltet sein!). The mail should contain the type of aircraft, the type of the device sourcing the FLARM data stream, and the address of the client in full. When I have no other info I will ship to that address. Please indicate what method of payment will be used (bank account or PayPal), as this might influence fees.

    With orders from abroad (outside Germany) I expect advance payment against a proforma invoice.

    Clients from abroad, who are natural persons, not firms, will have to pay German VAT.

    Clients from outside the Common Market, who are legal persons, firms, do not have to pay German VAT, however, all customs dues are to be paid by the client.

    Clients from inside the Common Market, who are legal persons, firms, are exempted from German VAT only, if the order provides the their valid VAT number.


    Shipping will always occur as an insured parcel. Please be warned, as experience shows, mailing fees, PayPal fees, bank transfer fees to countries abroad may be considerable.


    The How2Soar flash is compatible with (has been fitted to) the following plane types:



    It is pretty evident why people ask me if the flash impedes the field of vision in a plane.

    Well, certainly, there is something new in your field of vision, but the obstacle is probably much, much smaller than you imagine. If you have a compass on top of your instrument panel, the flash sort of hides behind it.

    The picture to the right is taken in Holger Backs LS10 (CEO at DG Flugzeugbau), camera held at the pilot's eyes position. Just the upper edge of the CFRP-boat is visible at all.

    You may test this easily by your own. Fetch a piece of card-board and cut it to the size 6 * 16 cm and plug it into your cockpit instead of the boat.





    People keep asking me about perceptibility and detectability of the LEDs. How bright are they ? Are they visible in the air ?


    Here is what I know :



    When the battery pool in your ship can feed app. 300 mA permanently into the flash, you should do exactly that. That way people with a poor FLARM (there are by far too many of those) or people with no FLARM at all (there are too many of those also) get warned too.

    However, most glider pilots do not suffer from such excess battery power. Unused battery capacity of 5 - 10 Ah is scarce.

    In my DG I do not have such an opulence of energy, a constant loss of 300 mA throughout the flight cannot be tolerated, even as I buffer my batteries with solar panels.

    So what's to be done ?


    Flarm Rechenknecht Vergleich

    The FLARM is source to a data stream obeying the NMEA protocol, issuing bulks of data every second. One type of data record among those in the bulk are PFLAA records.

    Each such PFLAA record contains information about one plane in the reception area. Up to 50 planes may be followed by the FLARM at any one time. Each PFLAA record holds information regarding relative position of its plane to the receiving plane (that is you), course, relative altitude, and the level of threat generated by this plane (0 = no alarm - up to - 3 = urgent), corresponding to the FLARM documentation (Level 1 - time to crash 19-25 sec, Level 2 - time to crash 14-18 sec, Level 3 - time to crash 6-8 sec).

    Thus these data records provide the means to continuously construct and monitor the air traffic situation : 'situational awareness'.

    They also contain information about ADS-B data and about FLARMs in stealth mode.


    Hello dear CalGnome client,

    I am trying to get in touch with you because I have identified a problem with the CalGnome program which I would like to fix soonest.


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