VTOL Explorer Build Instructions
The VTOL Explorer (Vertical Take Off and Landing Explorer) is a “kit bash” project based on the Flite Test Explorer. It is designed to be easy and fun to fly in all flight modes from hover to Fast Forward Flight (FFF).
As an airplane, the VTOL Explorer is very normal. It does all the typical maneuvers you would expect of a trainer including inside loops, rolls, and inverted flight (barely). It is a bit heavier and more complex than a typical trainer, and is not very fast. The rate of climb is modest. Flight times are about 7 minutes with a 3,300mAh battery and good safety margin.
As a quad-copter the VTOL Explorer is very easy to fly. It is mostly auto stabilized by the onboard electronics. I would not recommend it as your first quad-copter only because there are excellent, cheap, and extremely durable quad-copters that you can learn to fly in your living room. If you can comfortably hover tail in, meaning the aircraft is facing away from you, then you will have no difficulty hovering the VTOL Explorer.
Transitions from hover, to SFF (Slow Forward Flight), to FFF (Fast Forward Flight), and back again, are as easy as flipping a switch and flying the plane. SFF is the easiest flight mode, ranging from gentle cruising in airplane mode to a nose high hover.
The VTOL Explorer handles a modest amount of wind with ease. It flies at any speed from slowly backwards to full forward flight. You can point the nose into the wind, match your airspeed to the wind speed, and hover for a takeoff or a landing.
A video of the VTOL Explorer in flight is available here:
The PDF file of the build instructions is too large to be included here. It, and all of the related files can be found here. If the links don't open with a left click then try a right click and open in a new tab:
OpenAero-VTOL Support Thread. Get the latest firmware and ask your questions about the firmware here:
OpenAero-VTOL GUI Support Thread. Get the latest GUI (Graphical User Interface) and ask your questions about the GUI here. The GUI is not absolutely necessary, you can always enter the user parameters via the 4 button and LCD interface on the KK2 board. Recommended for users with more advanced PC skills:
The build instructions are based heavily on the excellent Flite Test build video located here:
The original build thread can be found here:
Weight ready to fly: 3.47 pounds with battery.
Weight without battery: 2.9 pounds
Wing Area: 398 sq. in.
C.G.: 5.25” behind the wing Leading Edge
Typical Flight Time: 7 minutes
Lift Motors: Flite Test Power Pack D, (4) Emax 2213-935kv
Lift ESCs: (4) Emax BL Heli 20 amp XT-60
Lift Propellers: Emax 10x4.5, (2) CW, (2) CCW
Forward Thrust Motor: Flite test Power Pack C, Emax GT2215/09
Forward Thrust ESC: - Emax BL Heli 30 amp ESC
Forward Thrust Propeller: 9 x 6 EP, APC
Battery: 3.3Ah, 25-50C or better
Servos: (4) Emax ES08A II 8.5g
Flight Controller: KK2.1.5 or KK-mini
Flight Controller Firmware: OpenAero-VTOL
3.8W - All motors off
204W, 11.48V, 17.8A – Hover Power
450W, 10.98V, 41A – Full throttle, hover motors only
6.5 lbs. – Maximum Hover Lift
101W, 11.64V, 8.7A – Minimum forward flight at cruise, forward thrust motor only
225W, 11.43V, 19.7A – Full throttle, forward thrust motor only
Most of these parts can be obtained from the Flite Test store, and equivalent parts are broadly available. Some of the simplest and most common parts such as glue and tape are not listed. Obviously, you will need to make substitutions to match your radio.
FT Explorer Speed Build Kit, $39
Power Pack D (Standard Quadcopter), $120
Power Pack c (Fixed Wing Large), $65
FT Elements Simple Firewall , 4 each, $5 ($20 total)
Female XT60 Connectors, $4.50
Male and Female Bullet Connectors, 3.5mm, 12 pairs, $5.25
Flite Test Water-Resistant Foam board by Adams (50 pack) , $80.00 (Need 1 sheet)
Turnigy nano-tech 3300mah 3S 25~50C Lipo Pack, $28.34
Hobbyking KK2.1.5 Multi-rotor LCD Flight Control Board With 6050MPU And Atmel 644PA. $19.99
ZYX-S S.BUS Connection Cable, $3.47
Orange Rx R620X V2 6Ch 2.4GHz DSM2/DSMX Comp Full Range Rx w/Sat, Div Ant, F/Safe & SBUS (Any size RX with S.bus and satellite capability will work), $20.64
OrangeRx R110X DSMX/DSM2 Compatible Satellite Receiver (Any compatible satellite RX will work) $12.79
USBasp AVR Programming Device for ATMEL Processors, $3.99
Colored Acrylic Packing Tape, 2” wide, $3.95 each
Amazing Goop, $8.00, Any hardware store
12 AWG Primary Wire, Any Color, $5.00, 1 foot, Any hardware store
18 AWG Primary Wire, Any Color, $5.00, 17 feet, Any hardware store
The unique aspects of the VTOL Explorer design are offered freely for use by anyone, commercial or private. If Flite Test wants to offer a speed build kit for the motor pods, etc. they are welcome to do so.
The base Explorer design is the property of Flite Test.
The KK2.1.5 and KK-Mini design are the property of HobbyKing.
The OpenAero-VTOL (OAV) Firmware is open source and subject to the terms and limitations in the OpenAero-VTOL User manual.
If FliteTest wanted to offer the KK2 pre flashed with OAV, and possibly even loaded with the specific user parameters for the VTOL-Explorer then I would be happy to work with them to make that happen. Flashing the firmware is a significant entry barrier for many new users.