Setting the Failsafe
Something a newcomer to RC flying may forget to do – configure the failsafe settings.
So what are failsafes? If an aircrafts receiver loses its radio signal connection with the pilots transmitter then the receiver should have been configured to reduce motor/engine power and move control surface servos to some particular position(s).
In other words a failsafe is just a guess that you have to make about what you want your aircraft to do if your transmitter stops wotking. And transmitters can be dropped, their batteries can go flat and aircraft can fly out of their range – so its worth setting failsafes.
In fact CAP658 says:
“Any powered model aircraft fitted with a receiver capable of operating in failsafe mode should have the failsafe set, as a minimum, to reduce the engine(s) speed to idle on loss or corruption of signal.”
How you go about setting the failsafe of a particular aircraft depends on the make of the radio equipment. Please refer to your manuals for specific instructions. Or even easier – just google for a Youtube video.
Faster than the wind (would be better)
Ever seen a fast moving RC plane suddenly tumble to the ground out of control? This video looks at one possible cause – and you get to see a spectacular crash as a bonus 🙂
If an aircraft is flying in the same direction as a strong wind is blowing then the aircraft may be moving over the ground quite quickly. – this can confuse the pilot into reducing power until the airpseed is too low and a stall occurs. In other words – fly faster than the wind when the wind is pushing you along.
Is it worth £20 to find your plane?
In the summer months when the farmer’s crops are knee high and taller… anyone who has ever searched for a downed plane will know how difficult it can be.
And of course it’s important to avoid disturbing farmer’s crops as much as possible during the search.
There are a number of devices available on the market which can be used to find lost RC aircraft. There are three basic types of device – wireless trackers, GPS trackers (typically using mobile phone signals) and straightforward “beepers” which use an audible signal.
This is about the DroneKeeper Mini 2 – a “beeper” device.
I prefer simple solutions. I don’t want the hassle of extra gear to bring to the field like a wireless detector and I don’t want to worry about mobile phone coverage. I don’t want any more batteries to charge. I just want to stick something in/to my plane which will help me if I lose it. So I’ve gone with a beeper – the DroneKeeper Mini 2.
Overview of DroneKeeper Mini 2
Made in South Korea and sold by NicheMall.
The device has two modes in the way it can be used – Wireless Mode and Wired Mode. These are confusing names not least because in both modes the device can be wired using its USB lead for continuous recharge (DC 5v to 9v from a BEC or receiver channel).
Wireless Mode is about sounding an alarm if a period of time elapses without any movement being detected.
Wired Mode is about sounding an alarm if the pilot moves a switch on his radio.
Which is the best mode to use? It depends.
If you have a spare channel on your receiver then probably Wired Mode is best – you normally decide when it beeps and you can shut it up from your transmitter if it does start beeping (unless its beeping is due to power failure).
In Wireless Mode it can start beeping because you have been waiting too long for your turn to take off. And to silence the device in Wireless Mode you have to switch the device off using its tiny red slider switch. On the other hand with Wireless Mode its possible to simply velcro the device to a model with no wiring needed.
Weight: 9g with battery and with USB lead connected for continuous charging.
Length 35mm (additional 16mm with USB lead connected), Width 15mm, Height 12mm
Wireless Mode (better name might be “No Movement” mode) [default mode]
In Wireless Mode you can charge the device from a USB port of a computer and then simply velcro the device to a model without needing to connect anything electrically. But probably better to connect it up in the plane for recharging so you don’t need to remember to charge the device before leaving home.
According to the maker when used only with its included rechargeable coin cell battery (i.e. not connected for recharging):
o takes 1 to 1.6 hours to charge,
o lasts 20 to 40 hours if the alarm doesn’t go off,
o lasts 3 to 5 hours sounding the alarm. It has a low voltage alarm if no external battery is connected.
Wireless Mode sounds alarm:
• If no movement after configurable time interval (choices are 30secs [default], 1min, 3mins, 5mins, 8mins)
• If no power (if connected for continuous charging)
• Regardless after configurable time interval from switch on (choices are 20mins [default], 40mins, 60mins)
I think the “regardless after configurable time interval” is about covering for the situation where the model is dangling from a tree and being blown around by the wind.
Wired Mode (better name might be “User Triggered” mode)
Must be connected to a PWM channel of the receiver. This provides both a PWM signal and power to the device.
Wired Mode sounds alarm:
• If signal received from receiver (caused by flicking switch on transmitter or by failsafe. *See note below.)
• If no power
*Note: In Wired Mode you should configure the receiver’s failsafe to tell the device to start beeping in the event of radio signal loss – otherwise if you drop your transmitter then you may need to wait a long time for the aircraft’s battery to die before the beeping starts. Always good to check your failsafes occasionally anyway.
Early days for me with this thing. I’ll update this article at some point in the future when I know how well they work in practice. But so far I’m quite impressed. It seems to have been well thought out with all eventualities covered.
You don’t need a special programming card or battery charger. Configuring it (modes and times) is a bit fiddly but not too bad – its about touching a contact with a wire and counting beeps to move through the available options. Should only need to do this once before installing into an aircraft.
You can fix it to your plane in such a way that you can almost forget about it until you need its help. You do need to turn it on and off for each flight – and (as long as it’s connected for continuous charging) the device reminds you to do this by beeping in both cases.
The alarm beep isn’t as loud as I expected but loud enough. I’ve installed the device inside a foam fuselage and inside a plastic fuselage and the sound is still penetrating enough to be heard across my house.
When installing you need to remember to give yourself easy access to the red on/off slider switch. My only quibble with the device so far is you move the switch to the left for on and to the right for off – seems the wrong way around to me!
Connecting for continuous charging makes a lot of sense to avoid the hassle of charging up the device before each trip to the flying field. Connections for charging can be made to a 5v/6v BEC or to a spare channel on your receiver. Connecting to a spare channel gives you the choice of Wireless Mode or Wired Mode. If there isn’t a spare receiver channel and your BEC is buried inside the aircraft then it’s possible to use a Y servo splitter cable to tap into the power being used by a channel already in use – although this would prevent the use of Wired Mode. By the way the device is protected against Over Voltage. Don’t ask me how I know.
The device comes with its own special USB cable. To connect this to a receiver you will need a male/male servo cable.
For Youtube review see CurryKitten video:
For full details, user instructions and order form see NicheMall website:
As of 28/2/2019 the price is about £20 including postage. Mine took a week to arrive from ordering online.
And no, I’m not on commission and will not benefit in any way if you buy one!