VORSim

Radio navigation clicks when you fly it, not when you read about it.

VOR Sim is a procedure trainer for iPhone and iPad. A light flight model sits
behind a full six-pack panel, a moving map, a synthetic outside view and a
GNS 430-style GPS, so the needles stay the thing you have to concentrate on.
Nothing to configure, no aircraft to buy, no scenery to download: press START
and intercept something.

THE PANEL
• Classic VOR head (NAV1) with a rotatable OBS ring, CDI and TO/FROM flag
• HSI (NAV2) with course needle, deviation bar, heading bug and an ADF pointer
• Twin-needle ADF: tune two NDBs and cross their bearings for a position fix
• The ADF card is fixed, slaved to the compass (RMI) or set by hand — the three
ways a real ADF head is read, one knob apart
• Directional gyro that precesses about 10° in 15 minutes, and has to be reset
• Airspeed with an RPM sub-dial, attitude, altimeter with hPa subscale, VSI and
turn coordinator
• Spread two fingers on the panel and the three nav heads take the whole
screen, which on a phone is the only way to read half a dot; the V1 · V2 ·
ADF buttons under the panel decide which of them are up and how the width is
shared — V2 steps HSI → second VOR head → off, ADF two needles → one → off
• Every card and ring turns under the finger: the OBS ring on the VOR head and
the HSI, and the ADF card, which takes itself off the compass when you do

REAL NAVAIDS
• About 17 000 airports and 10 000 VOR and NDB stations from OurAirports, all
bundled, all offline. Positions, idents, frequencies and runway directions
are real
• Long press a VOR on the map to tune it on NAV1, then NAV2; long press an NDB
and it goes to the first ADF needle, then the second
• Long press an airport to fly direct to it

MOVING MAP
• Your aircraft, its breadcrumb track and every station, draggable — build an
intercept in seconds and drag the aeroplane back to fly it again
• The selected OBS course drawn through each VOR with TO/FROM arrows and radial
numbers pinned to the screen edge
• A chart scale bar you can long press and slide to zoom
• Or take the ground away: a second press of MAP leaves the stations, radials,
track and airspace on black, which is how a radial is easiest to read

GNS 430
• Direct-To, a flight plan with automatic leg sequencing, OBS suspend, CDI
source switching between GPS and VLOC, COM and NAV tuning
• Any bundled ident can be typed in, with a match list from the database

FLYING IT
• Tilt the device like a yoke — tilt is elevator, rotate is ailerons — or use
the on-screen stick, rudder and throttle. Hardware keyboards work too
• Controls are damped the way an aeroplane is: an input arrives over about a
second, and the turn builds up after it
• Engine sound synthesised from the rpm, from a lumpy idle to full power
• Wind with gusts, 1–4× time compression, a stopwatch for timing a hold
• Power off, the nose has to come down; below about 45 kt the wing stalls, with
aileron on it spins, and the ground ends the flight
• A turn costs what it costs: 1.4 g at 45° of bank, and either the nose falls
or the speed does

OUT OF THE WINDOW
• Look out over the cowling — the nose is the attitude reference in a real
aeroplane, and where the horizon sits above it is your pitch
• Or switch to the glass panel: the nose goes, and the horizon, a pitch ladder,
a bank scale and boxed speed, height and climb are painted on the window, so
the view can be flown on its own
• The ground under you is the real countryside, from the map

The training area centres on your position, or on EDAZ Schönhagen. Switch on
"Reset moves you somewhere new" and every reset deals the exercise at a real
aerodrome somewhere else in the world, with the real VORs around it.

Made by a pilot, for pilots and for students working on the instrument rating.

IMPORTANT — the airspace, and the exercise stations dealt by a reset, are
invented for training. Nothing in this app may be used for real navigation.