My first project - Wireless Airspeed indicator

Hello, I have been making some of the available Arduino projects for a while, but I got an idea for my first complete project.

As flying is one of my hobbies, I found out our club would have great benefit if glider towing winch operator would know the airspeed of the glider in a tow.

The idea is putting one Arduino UNO on a glider and connect it to a MPXV7002DP differential pressure sensor and a YKS 3DR Radio Telemetry transmitter. On ground (on winch) there would be another UNO with YKS 3DR receiver and LCD display showing the airspeed of a glider.

Is it possible to combine all that or there would be problems?

I was also thinking about adding a GPS, barometric pressure module and a MicroSD card reader to the glider UNO and give it a logger function too.

Has anyone done that and would like to share the project?

Being a ex private pilot also having some knowledge about towing and winching planes I say directly: don't proceed.
It will not be legal to use in any country. Suppose something goes wrong in that unit and the winch operator makes a bad decision?
In case of a crash, will You stand up and take responsibility for a home made device that might have caused the crash?

No, use approved air radio equipment for communication.

We do use radio as main communication. This is just additional gadget and is here legal as such.

May I ask what Your country is?
Reading and watching numerous of crash investigations and the reasons behind the crashes I know that "well made" but not certified parts are banned.

I don't see how my location is important for the project. You can see many gliders in Europe have installed uncertified android units (mobile phones, tablets) with XCSoar software and as long as it is being used as aditional gadget it is not forbidden to have. Standard analog instruments are mandatory though.

I leave Your question unanswered.

Has anyone done that and would like to share the project?

The code is not difficult really, although you should appreciate that a UNO is a poor choice for such an important application.

What experience do you have in radio systems, GPSs and Arduino in general ?

Well this is my first project from ground up. I have been playing around with Arduinos for the last two years but 100% by following instructions and using preprogrammed codes. Also I'm in RC all my life. GPS is just an idea, main job is measuring airspeed and sending the value to the display 2-3 hundred meters away. Do you think Mega whould do better?

My thoughts...outside any legal discussion :slight_smile:

this sounds like a straightforward project--and I have something very similar working (telemetry for a race car with wireless data transmission, GPS, speed sensors, etc.)

  1. the sensor you indicated I believe is good for a differential pressure of up to 7 inches of water (fraction of PSI)
  2. Pv (velocity pressure) for an airspeed of 100 mph STP, is around 4.8 inches of water so you may be OK with that sensor, but I'm not sure what speeds you are looking at measuring
  3. I'm not sure about that transceiver, I use EBYTE (E32-915T20D for example) and have very good luck with them. Simple device where you write to a serial port. EBYTE.H library has examples in how to program and send data
  4. making a ground-based device to read the sent data is fairly straightforward where you read from the EBYTE's serial port and display appropriately
  5. GPS sensors are relatively easy to get working (TinyGPS lib has great examples).
  6. depending on how you want to display the air speed and such, a display 2.8" TFT for example are common and easy to get working--the ILI9341 lib for example has good examples
  7. NANO's will easily do the job, but if you want SD support, pretty graphics and fonts on you ground display, forget Arduino and move to a Teensy 3.2 (I realize this point will start a war with some on this forum :slight_smile:

Not sure if this helps...

You guys like to complicate everything.

Just translate the winch RPMs to tow speed. Works for every glider.

You guys like to complicate everything.

Just translate the winch RPMs to tow speed. Works for every glider.

Fairly certain that is how it is already done.

Yup...checked wiki....

Gliders are often launched using a stationary ground-based winch mounted on a heavy vehicle.[31] This method is widely used at many European clubs, often in addition to an aerotow service. The engine is usually powered by LPG, petrol or diesel, though hydraulic fluid engines and electrical motors are also used. The winch pulls in a 1,000 to 2,500-metre (3,000 to 7,500 ft) cable, made of high-tensile steel wire or a synthetic fiber, attached to the glider. The cable is released at a height of about 35% of the cable length after a short, steep ride

Apart from that,any pilot worth their salt will tell you a quick glance at the common guages is an important part of any takeoff or landing.
The last thing one needs is to be trying to figure out what some add on guage is supposed to read or be doing.

\our club would have great benefit if glider towing winch operator would know the airspeed of the glider in a tow.

This suggests that you intend to use the project for actual flight operations.

That has all kinds of legal and liability issues - possibly the most important issue is that if it goes wrong, it's you that did it. That alone is a good reason to buy commercial, certified products for potentially dangerous operations. If the sensor fails and the glider crashes, you can sleep well knowing you did the right thing when you picked and installed the commercial sensor.

This is just additional gadget

This, and more of your comments, suggest it's just an extra that is irrelevant to the operation.

If it is so beneficial for the winch operator to know the air speed of whatever they're towing, why don't they know it now? How do they now operate their winch in a safe and effective manner?

I can understand lots of little gadgets that you may want to add to an aircraft, that are not used for actual flight operations, and are thus perfectly legal. Such as a GPS location/altitude logger, or other additional sensors such as an air speed sensor (as long as it can be mounted to the aircraft in a proper way) that you just log to look back at your flight data after you land for your own entertainment. That is the kind of gadget you should be looking to build.

Just translate the winch RPMs to tow speed. Works for every glider.

At first, yes. Later, when the plane has gained altitude.... Plot the figure and check the arithmetics when 35% of the wire is home on the drum.

Nevertheless, for me it's out of question to support a person new to electronics/programming to even think of it.
No club puts an unexperienced newbie to run the winch......

Radio communications are used for winch operating, and it is always going to be primary. Only benefit of this new gauge would be less radio communication - a bit relief on frequency.
RPM translation can't measure airspeed

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