This inheritance list is sorted roughly, but not completely, alphabetically:

CNavigation::Aircraft	This extremely simple class holds a few numbers that describe an aircraft
CGeoMaps::Airspace	A very simple class that describes an airspace
CUnits::Angle	Convenience class for angle computations
CNavigation::Atmosphere	Atmospherical data
CNavigation::BaroCache	Cache relating geometric and barometric altitude information
CUnits::ByteSize	Convenience class for size_t
CTraffic::ConnectionInfo	Connection to a traffic data receiver
CTraffic::ConnectionScanner_Abstract	Connection Scanner
CTraffic::ConnectionScanner_Bluetooth	Connection Scanner: Bluetooth Devices
CTraffic::ConnectionScanner_SerialPort	Connection Scanner: SerialPort Devices
CFileFormats::CUB	CUB file support class
CFileFormats::DataFileAbstract	Base class for file reading classes
CFileFormats::CSV	CSV file support class
CFileFormats::CUP	CUP file support class
CFileFormats::FPL	FPL file support class
CFileFormats::MBTILES	Utility class for databases in MBTILES format
CFileFormats::MapURL	MapURL file support class
CFileFormats::PLN	PLN file support classq
CFileFormats::TIFF	TIFF support
CFileFormats::GeoTIFF	GeoTIFF support
CFileFormats::TripKit	Trip Kit
CFileFormats::VACCollection	Collection of visual approach charts
CFileFormats::ZipFile	ZIP Archive
CWeather::Decoder	METAR/TAF decoder
CDemoRunner	Remote controls the app and takes screenshot images
CUnits::Density	Convenience class for density computations
CWeather::DensityAltitude	This class calculates the density altiude according to temperature, QNH, Altitude (and dewpoint)
CUnits::Distance	Convenience class for distance computations
CDataManagement::Downloadable_Abstract	Abstract base class for Downloadable_SingleFile and Downloadable_MultiFile
CDataManagement::Downloadable_MultiFile	Group of closely related downloadable items
CDataManagement::Downloadable_SingleFile	Downloadable object
CFileLibraryModel	List of the entries of a file-based library
CTraffic::FlarmnetDB	Flarmnet database
CFlightlog::Flight	A single flight log entry
CFlightlog::FlightDetector	Abstract base class for automatic flight detection strategies
CFlightlog::AirplaneFlightDetector	Flight detection for powered aircraft
CFlightlog::FlightLogExportForeFlight	ForeFlight Logbook Import CSV export format for the flight log
CFlightlog::FlightLogExportJSON	JSON export format for the flight log
CFlightlog::FlightLogStorage	SQLite-backed storage for the flight log
CFlightlog::FlightRecorder	GPS track recorder and IGC file manager
CNavigation::FlightRoute	Intended flight route
CPositioning::Geoid	Provide geoidal separation according to https://en.wikipedia.org/wiki/Geoid
CGeoMaps::GeoJSON	GeoJSON file support class
CGlobalObject	Base class for global singleton objects
CDataManagement::DataManager	Manages the list of geographic maps
CDataManagement::SSLErrorHandler	Handles SSL error
CFlightlog::FlightLog	Flight log manager with pluggable automatic flight detection
CGeoMaps::GeoMapProvider	Provides geographic information
CNOTAM::NOTAMProvider	Manage NOTAM data and download NOTAM data from the FAA if required
CNavigation::Clock	This extremely simple class give accss to time and offers a few time-related functions
CNavigation::Navigator	Main hub for navigation data
CNotifications::NotificationManager	This class manages notifications and presents them to the GUI
CPlatform::FileExchange_Abstract	Interface to platform-specific file exchange functionality
CPlatform::FileExchange	Implementation of FileExchange for Android devices
CPlatform::FileExchange	Implementation of FileExchange for Android devices
CPlatform::FileExchange	Implementation of FileExchange for Android devices
CPlatform::FileExchange	Implementation of FileExchange for Android devices
CPlatform::FileExchange	Implementation of FileExchange for Android devices
CPlatform::FileExchange	Implementation of FileExchange for Android devices
CPlatform::PlatformAdaptor_Abstract	Interface to platform-specific functionality
CPlatform::PlatformAdaptor	Implementation of PlatformAdaptor for Android devices
CPlatform::PlatformAdaptor	Implementation of PlatformAdaptor for Android devices
CPlatform::PlatformAdaptor	Implementation of PlatformAdaptor for Android devices
CPlatform::PlatformAdaptor	Implementation of PlatformAdaptor for Android devices
CPlatform::PlatformAdaptor	Implementation of PlatformAdaptor for Android devices
CPlatform::PlatformAdaptor	Implementation of PlatformAdaptor for Android devices
CSensors	Sensor data
CGlobalSettings	Global Settings Manager
CGeoMaps::GPX	GPX file support class
CNavigation::Leg	Leg in a flight route
CLibrarian	Manage libraries and text assets
CWeather::METAR	METAR report
CUi::NameFilterProxyModel	Filters a list model by a fuzzy name match
CUi::DistanceSortProxyModel	NameFilterProxyModel that orders rows by distance to a reference position
CNOTAM::NOTAM	This extremely simple class holds a the data item of a NOTAM
CNOTAM::NOTAMList	A list of NOTAMs
CNotifications::Notification	Base class for all notifications
CNotifications::Notification_DataUpdateAvailable	Notification for available map & data updates
CNotifications::Notification_OversizedMap	Notification for oversized aviation maps
CWeather::Observer	Holds and updates METAR and TAF for a given waypoint
CWeather::ObserverList	Up-to-date list of all METAR/TAF stations
CTraffic::ConnectionInfo::OgnInfo	Constructor parameter for OGN connections
CFileFormats::OpenAir	OpenAIR file support class
CTraffic::PasswordDB	Password database
CPositioning::PositionInfo	Geographic position
CPositioning::PositionInfoSource_Abstract	Abstract base class for all classes that provide geographic position information
CPositioning::PositionInfoSource_Satellite	Satellite Navigator
CPositioning::PositionProvider	Central Position Provider
CUnits::Pressure	Convenience class for pressure computations
CUi::QSortFilterProxyModelForeign	Makes QSortFilterProxyModel known to the QML type system
CNavigation::RemainingRouteInfo	Info about remaining route
CUi::ScaleQuickItem	QML Class implementing a scale for a Map
CUi::SideviewQuickItem	QML base class for lateral airspace view
CUnits::Speed	Convenience class for speed computations
CWeather::TAF	TAF forecast
CUnits::Temperature	Convenience class for temperature computations
CGeoMaps::TileHandler	Implementation of QHttpEngine::Handler that serves mbtile files
CGeoMaps::TileServer	HTTP server for mapbox' MBTiles files
CUnits::Timespan	Convenience class for time computations
CFlightlog::TrackPoint	A single point along a recorded flight track
CTraffic::TrafficDataProvider	Traffic receiver
CTraffic::TrafficDataSource_Abstract	Base class for all traffic receiver data sources
CTraffic::TrafficDataSource_AbstractSocket	Base class for all traffic receiver data sources that receive data via network sockets
CTraffic::TrafficDataSource_BluetoothClassic	Traffic receiver: Bluetooth Classic connection to a FLARM/NMEA source
CTraffic::TrafficDataSource_BluetoothLowEnergy	Traffic receiver: Bluetooth LE connection to a FLARM/NMEA source via the "Nordic UART Service"
CTraffic::TrafficDataSource_Ogn	Traffic receiver: OGN glidernet.org via internet connection
CTraffic::TrafficDataSource_Tcp	Traffic receiver: TCP connection to FLARM/NMEA source
CTraffic::TrafficDataSource_Udp	Traffic receiver: UDP connection to GDL90 source
CTraffic::TrafficDataSource_File	Traffic receiver: Simulator file with FLARM/NMEA sentences
CTraffic::TrafficDataSource_SerialPort	Traffic receiver: Serial Port Connection to a FLARM/NMEA Source
CTraffic::TrafficDataSource_Simulate	Traffic receiver: Simulator that provides configurable simulated data
CTraffic::TrafficFactor_Abstract	Abstract base class for traffic factors
CTraffic::TrafficFactor_DistanceOnly	Traffic factor whose distance is known, but not its bearing
CTraffic::TrafficFactor_WithPosition	Traffic factor whose precise position is known
CTraffic::TrafficFactorData	Plain-data record of a traffic factor
CTraffic::TrafficFactorData_DistanceOnly	Plain-data record of a traffic factor whose position is not known
CTraffic::TrafficFactorData_WithPosition	Plain-data record of a traffic factor whose precise position is known
CTraffic::TrafficObserver	Provides list of traffic, sorted by relevance
CTraffic::TransponderDB	Transponder database. This class implements an algorithm to decode the 24-bit transponder address to a callsign for some countries. It is based on code from dump1090 at https://github.com/mutability/dump1090/blob/unmaintained/public_html/registrations.js under GPLv2 license
CGeoMaps::VAC	Visual approach chart
CGeoMaps::VACLibrary	Library of visual approach charts
CUnits::Volume	Convenience class for volume computations
CUnits::VolumeFlow	Convenience class for volume flow computations
CTraffic::Warning	Traffic warning
CGeoMaps::Waypoint	Waypoint, such as an airfield, a navaid station or a reporting point
CGeoMaps::WaypointLibrary	Library of user-defined waypoints
CUi::WaypointSearchModel	Item model over all waypoints known to the app, for search lists
CWeather::WeatherDataProvider	WeatherDataProvider, weather service manager
CWeather::Wind	This extremely simple class holds the wind speed and direction