Navigation has never been that simple!

Pilot's Ruler


The SMART ruler for VFR pilots: all functions on one instrument,
fast read-out, simple in use

This ruler has been designed to offer pilots maximum support in the simplest way, during flight preparation and in flight.
It enables pilots to solve navigation problems and provides useful information both at a glance, in only a few seconds, with only one instrument.

see larger picture

FAST read out and SIMPLE in use!
Pilots can now fly safer and more relaxed and concentrate more on flying, less on calculating. See video -->

Pilot magazine UK wrote:
There are pilot rulers and there is The Pilot's Ruler"





Intergrated Portractor
VFR Cruising Levels Europe / UK / USA *
ATC Light Signals
Special Transponder Codes Europe / USA *
Morse Code
Emergency Frequency
Landing Cross Wind Table
Distance Ruler, for chart scale 1/250 000
Distance Ruler, for chart scale 1/500 000
Easy convert to chart scale 1/1 000 000
Flying Time (EET) Table, for Ground Speeds from 50 up to 180 knots
Calculation of Ground Speed
Calculation of Head- or Tailwind component

* depending on region of purchase (EU or USA)

DELIVERY - 3 types

A. Ruler EU + user guide in English
B. Règlette EU, avec guide de l'utilsateur en Français
C. Ruler USA + user guide in English

Colour, for good readability
Flexible material to make good contact with the aeroautical chart
Soft, no risk to scratch the wind screen when stowed on the dashboard
No batteries
No sliding parts
No keyboard input
No sunlight reflextion

Although the ruler was designed to be easy to use this page offers some additional tips and information.


There are two distance measuring scales on the ruler:
- for the Terminals Area Chart, scale 1/250 000
- for the Sectional Chart (SEC), scale 1/500 000
- for World Aeronautical Charts (WAC), scale 1/1 000 000, simply use the measuring scale 1/500.000 and multiply all distances by 2 (two).

The DISTANCE RULER and EET table can both be used for flight preparation and during flight.

The EET table (expected-en-route-time, or flying time) for instant read out of the flying time to:
- final destination;
- next, or any, way point;
- any reporting point, as asked by ATC.
-> Enter distance and ground speed and read out immediately the expected flying time.

The EET table can also be used for calculation of:
- ground speed and
- head- or tailwind component during flight, when no other measuring means (DME, GPS) are available.
-> Look up in the table the flown time for a known distance (between two way points) and read out the corresponding ground speed (GS).
-> The difference between the TAS and GS determines the head- or tailwind component.

In the EET table all results were rounded down to the minute. Because at some points three of the same results (figures) appeared for three different ground speeds, the seconds were also added.
(for example: given a distance of 5 nm and the ground speeds of 80, 90 & 100 kts the (rounded) result was three times 3’ (minutes), which was rather confusing)


The integrated protractor is of the standard type, North is held up. Place it, hole over point of departure, over the line that connects departure (or actual position) to destination and read out the track.
Or use the side of a pencil to connect departure and destination.

If the Track line is behind the ruler (blind zone) rotate the ruler 1/4 to the left and use the red numbers to read the track.

See figure below:

click to call image

The use of flight levels is one way to help preventing collision between aircrafts flying opposite tracks.
Most common system used world wide is the East/West orientated Semi Circular System, however in some countries a different system can be implied.

uses the general East/West Semi Circular System.

Southern Europe: Italy, Portugal, and some parts of France *:
uses a North/South orientated Semi Circular System.
* these regions are marked on the aeronautical charts.

United Kingdom:
uses the Quadrantal System, witch divides the airspace into four flying directions (the use of this system is advised for VFR flights outside controlled airspace).

uses also the East/West Semi Circular System but here the Transition Altitude (altimeter setting on QNH) is only at 18.000 feet ASL.

China, Mongolia, Russia and many CIS countries:
use flight levels system in the metric system.

Flight Levels - General principle:


Transition Altitude (TA) varies in Europe and can be as low as 3.000 ft.
Remember to set the altimeter to 1013,25 mb/29,92 In Hg when passing the TA.
See also link below for more information concerning the subject.

It was interesting to learn that the aviation transponder was developed during World War II by the British and American military as a identification system to differentiate friendly from enemy aircraft.

World wide common codes are:
- 7500: Unlawful Interference (Hijack);
- 7600: Lost Communications (Radio Failure);
- 7700: General Emergency (Distress).

Beware not to dial these codes accidentally when changing from one to another required transponder code. Also do not select 'STANDBY' when changing codes because this will cause the lost of the target on the radar screen.

Specific codes:
- 7000 is the general VFR code for Europe, except in UK, where it is used an a general conspicuity squawk *
- 7041 is used in the London area by special rule,
- 1200 is the code for VFR flight in the USA when no code is assigned,
  in Canada when operating at or below 12.500 ft ASL,
- 1400 is used in Canada when operating VFR above 12.500 ft ASL,
- 2000 is the code when entering a SSR Area coming from a non SSR Area, also used for a non controlled IFR squawk code in ICAO countries,
  in Canada for non controlled IFR flights at or above 18.000 ft.

VFR transponder codes are used when navigating VFR in uncontrolled zones.

* Conspicuity Code
When operating at and above FL 100 pilots shall select code 7000 and Mode C except:
(a) when receiving a service from an ATS Unit or Air Defense Unit which requires a different setting,
(b) when circumstances require the use of one of the Special Purpose Codes or one of the other specific conspicuity codes assigned in accordance with the UK SSR Code Assignment Plan as detailed in the table at ENR 1-6-2-5 to ENR 1-6-2-10. When operating below FL 100 pilots should select Code 7000 and Mode C except as above. 
Pilots are warned of the need for caution when selecting code 7000 due to the proximity of the Special Purposes Codes.

It is good practice to always positively identify the beacon(s) which you are using during navigation, especially at regions with few visual navigation marks, where flying for a long time on the wrong beacon can lead to important off-track positions!

Possibly in a stressful situation some pilots will not be able to recall the emergency frequency.
Imagine a non controlled flight with no, or only air tot air, radio contact. If a emergency situation would occur, there will be no time to look up a FRQ from a ATC unit.
In that case best action is to dial 121.5Mhz, the international emergency frequency, witch is being monitored by (almost) any ATC unit.

Imagine this situation (it recently happened to one of our C150's!): you're flying the long final and cleared to land. Suddenly you lost radio contact, for whatever reason.
You will most probably receive from now instructions by light signals.
But what do they mean again???
No panic, your ruler has the answers!

Acknowledge by switching on and off your landing lights or by rocking the wings.

The graph is meant for quick calculation of landing cross wind. The use is simple:
-> Enter the reported surface wind from the airfield on the left side and follow the corresponding arc until crossing the straight line coming from the corresponding cross wind component. *
-> Now, at the intersection of the two lines go straight to the bottom of the graph and read out the effective landing cross wind.
See figure below.
If you're not good in mind calculation just visually project these givens on your gyro compass and count up/down to obtain the difference.

* Subtract/add wind direction by runway heading direction to obtain cross wind component.



More information concerning Flight Levels worldwide:

More information concerning the use of Transponder Codes worldwide:

To consult a electronic (internet) AIP from any country in the world. Some eAIP's are directly accessible, others require the creation of a (free) user account: