MGL Avionics User Forum

While taking out the EFIS to do some new wiring, I accidentally broke off the static line nipple. Is this something I can fix/replace by taking off the back cover, or do I need to send it to Michigan Avionics for repair?

Hi V.A. Long EZ,

Sorry to hear you broke the tip off the static sensor, my guess you would be better to get the unit fix with a new sensor, sending to MGL Dealer.

Rainer might have an other suggestion.

Others might find this a helpful hint.

I always use a hot air gun (or you could try a small hair dryer gun) to soften up the tubing, especially when it's old and it has a very strong grip on the sensors tip, make it softer with some heat and at the same time work it off the pressure sensors carefully to reduce the risk of breaking the tip off.


Cheers
JimJab

Thanks for the reply! I did read in the manual that for a “low performance airplane “, which I think the LongEz is, I could just leave it off and use cockpit air as a source. I just don’t like having something broken! I’ll standby for more input. I generally fly below 10,000’ and airspeed less than 150 knots. Only VFR too. Thanks!

Okay, correction time. It was the pitot sensor that broke off, not the static.That kind of changes the repair logic. Should probably send it off to Michigan Avionics.

DId you make any progress with your repair?

I just had a plane delivered that had an Enigma. Although the ferry pilot said it flew well there were a few quirky issues. He said the airspeed reading was erratic. So I decided to check the pitot static system. I tried to remove the Enigma but the builder left now service loops behind the panel and as such I ended up snapping off the pitot and static nipples.

The AOA ports were not being used so I had that sensor swapped for the pitot/static sensor (they had the same part number).
When testing the system I can apply slight pressure to the pitot port and the airspeed increases. However when I apply a slight vacuum to the static side the airspeed also increases. There is no change in the altitude reading.
Im wondering if the altitude data is obtained in another manor. I'm not able to fly the plane at the moment so cant test to see if the the altitude changes when off the ground.

Cheers
Rich

You will notice that the sensor you took out has a small hole drilled on the side that fits to the altimeter sensor - that's how the static pressure gets to that sensor. If you swapped sensors - make sure you drill that hole but CAREFULLY - if you drill too deep you will destroy the chip that resides in the center between the two ports.

Sadly these sensors can no longer be found (MPX12) so they are very precious.

On the sensor using in the lites - if you need to replace that sensor - we use the 3.3V version of this sensor - A type MP3V5010 from NXP.
We are having great difficulty finding stock of this part - you can now consider a type MPV5010 which seems easier to get. This is the 5V version.
It appears to be using the same silicon as the 3V version but with different trimming.
We tested it extensively here over a wide temperature range fitted to the lite that runs the sensor at about 3.4V - it appears to work fine and gives the same pressure range but with reduced ability to do negative pressures - but that is irrelevant for our application.

As part of the experiments with this sensor I also fiddled with the calibration to try an old idea - to calibrate the zero pressure point at two different temperatures to work out a simple linear compensation - based on the fact that temperature effects on the sensor appear very linear over a large range. So with the next release of firmware for the EFIS this will be part of it even for existing sensors. All it requires is for you to do a "zero" (a sensor calibration function in your setup menu) twice - at two different temperatures that are at least 10 degrees C apart (in any direction, does not matter).
This improves the zero point drift by at least a factor 10 - thus allowing the minimum airspeed reading to be brought down quite significantly.

rainier wrote: ↑Thu Apr 21, 2022 9:47 am You will notice that the sensor you took out has a small hole drilled on the side that fits to the altimeter sensor - that's how the static pressure gets to that sensor. If you swapped sensors - make sure you drill that hole but CAREFULLY - if you drill too deep you will destroy the chip that resides in the center between the two ports.

Sadly these sensors can no longer be found (MPX12) so they are very precious.

Thank you - I didnt notice but will make sure to put a hole (carefully) in the side.

Sorry for the late reply .... I sent the unit to the repair facility in Torrance, CA and got it back about 2 weeks late with a new pitot/static sensor and the firmware and data bases updated. Great work, so thanks Torrance (Hiram)! The only thing I found was the Hobbs/Maint/Tach hours were all reset to 0. Not a problem since I had a picture of the latest settings, so I reset them back to what they should have been.