12V backup for instrument pod

[MikeBoyette]

Most important instrument needs no battery. I hope you put a yaw string on your machine.

 

[samouced]

Most important instrument needs no battery. I hope you put a yaw string on your machine.

I can install a short rod in the top of the pod for a string. The right instrument has a slip indicator at the bottom too.

 

[MikeBoyette]

I can install a short rod in the top of the pod for a string. The right instrument has a slip indicator at the bottom too.

That’s awesome. I have actually flown a machine with just an airspeed indicator and slip string. That’s it. It was unnerving and I flew rather high without an altimeter.

 

[Abid]

I can install a short rod in the top of the pod for a string. The right instrument has a slip indicator at the bottom too.

If you are going to rely on that MGL ball to keep you coordinated. Good luck. Put a string or a flag. Trust me MGL software filter is all over with the vibrations from the gyroplane. Garmin and Dynon are solid. Kanardia is a close behind Garmin but MGL is way at the back. A $0.50 piece of yarn in the right spot never lies and is faster and more accurate than all of them.

 

[samouced]

Trust me MGL software filter is all over with the vibrations from the gyroplane.

I hope that the three rubber mounts that the pod is on would help with those vibrations. Ill install a string.

 

[Abid]

I hope that the three rubber mounts that the pod is on would help with those vibrations. Ill install a string.

It will for sure but it will still funk out from time to time. Are you using a separate AHRS sensor mounted remotely feeding this Infinity or is it built in version? If you are using SP-7 remotely mounted and if you mounted it in a good location that may work much better. The iEFIS with built-in sensor has no chance

 

[Resasi]

That’s awesome. I have actually flown a machine with just an airspeed indicator and slip string. That’s it. It was unnerving and I flew rather high without an altimeter.

My first solo forays on a Bensen were with ASI, ALT, and string, not quite as limited, pretty basic, but enough.

Your post, and Abids, has however set me thinking. During basic military training, in Chipmunks, we were subjected to limited panel in cloud and gradually reduced to almost nothing, until we finally lost control. One thing we never had was a string.

Now the string can be on a small mast...or simply taped to the windscreen. On Blue which has the MGL Explore EFIS and some issues with vibration, we are going to tape some wool/yarn to the bottom of the windshield.

I am just wondering, if the Chipmunk had had a small slip string taped to the windshield, when reduced to just airspeed on the instruments, would one would have been able to remain in control with just those two?

 

[WaspAir]

I am just wondering, if the Chipmunk had had a small slip string taped to the windshield, when reduced to just airspeed on the instruments, would one would have been able to remain in control with just those two?

Prop blast on the Chipmunk is likely to mess up the string indicatons. On gliders, helicopters (not in hover), and pusher gyros it works fine, or twin engine airplanes, but I've never tried one on a tractor single.

I think you would need a mag compass as well for it to work, anyway.

 

[samouced]

Here is the battery box I had made up in aluminum and powder coated.

 

[Sv.grainne]

I am installing two MGL Avionics Blaze instruments in a pod. I will also have an engine rpm and a rotor rpm gauge that will be powered by the Rotax 12V system. I would like to have a very small 12V battery backup (preferably in the pod) that can last 30 minutes or so If the Rotax power drops. It would also be nice to have to power the instruments with the engine off for adjustments. This battery will need to be able to remain connected to the 12V bus when the engine is running and not get over charged.

The two Blaze instruments will pull 95mA @12v minimum. I don't know how much the engine tach or rotor rpm gauges will pull.

Any ideas?

The battery looks really large to me. What AH rating? Looks like A lithium.

 

[Resasi]

I think you would need a mag compass as well for it to work, anyway.

Good point about prop blast, hadn't considered that.

We did have a large P type down between the legs, but by the time we had blanked most instruments were in actual cloud, the last thing we wanted to do was to be glancing down at a 'whiskey' compass which reacted slowly,...and was subject to compass errors.

 

[Resasi]

The battery looks really large to me. What AH rating? Looks like A lithium.

Check out the Earth X batteries Bobby.

Extremely light with power to spare.

 

[WaspAir]

Good point about prop blast, hadn't considered that.

We did have a large P type down between the legs, but by the time we had blanked most instruments were in actual cloud, the last thing we wanted to do was to be glancing down at a 'whiskey' compass which reacted slowly,...and was subject to compass errors.

I certainly understand avoiding the head motion.

For accidental IMC, I have heard it suggested that the compass sensitivity on a south heading, and known reverse error response to heading change, could help one hold a course while descending out of cloud. Never tried it for real.

 

[Resasi]

For accidental IMC, I have heard it suggested that the compass sensitivity on a south heading, and known reverse error response to heading change, could help one hold a course while descending out of cloud. Never tried it for real.

When I was in Saudi we had a Saudia 737 take off from Madina just before they closed for the night. They then had a total electrical failure and requested a return. The tower advised them to instead remain heading West VFR till they hit the coast, a very short distance, then turn South fly the short distance down towards Jeddah then see the city lights and land there.

The 737 did that but as he began turning South saw the standby compass with the N in the 'wrong' direction, got confused, so then did a 90 degree right turn instead and began heading North. The ground control eventually managed to get hold of them just before they went into Jordanian airspace, managed to turn them South and finally get them back to Jeddah.

 

[samouced]

The battery looks really large to me. What AH rating? Looks like A lithium.

It’s a lithium ion battery at 5Ah and 1.6 lbs.

 

[Resasi]

They cost a bit but for peace of mind...and lightness...

Lithium Batteries for Experimental Aircraft | EarthX Batteries

Our powerful and lightweight batteries are designed specifically for your aircraft starter or backup battery needs. Shop today.

earthxbatteries.com

 

[Sv.grainne]

Check out the Earth X batteries Bobby.

Extremely light with power to spare.

I have an Earth X battery but maybe is half the size of this one as best I can tell. I have more avionics so wondering what size battery .

All about weight and needed power.

 

[wolfy]

A yaw string is the only tool that's any use in a true vertical descent.
I beleive it's the most important instrument on a gyro.

wolfy

 

[MikeBoyette]

A yaw string is the only tool that's any use in a true vertical descent.
I beleive it's the most important instrument on a gyro.

wolfy

Agreed