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Fuel Level
#31
I don't recall any posts suggesting we remove the existing sight tube.

I check the sight tube regularly while in flight, and compare it with my Enigma reading.
The big advantage I see with the enigma is that I get an audible warning in my headset that say "Fuel Low" when I get down to 2 gallons.

I have my Enigma panel to show engine and rotor rpm, but I also have a back-up rotor tach that's completely independent and has it's own battery.

Just because you have extra pieces doesn't mean you're not safe, and hopefully some of the extra pieces enhance your safety.
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#32
Ron,

Not too keen on the "watch the clock " idea.
Have you flown the sector Whakatane to Kawerau? I did so years ago it a Victa 115, and being a crap instrument pilot, spent all the flight staring at the AH/DG etc, rarely looking at Ts, Ps, fuel or anything else.
That aeroplane had a terrible fuel gauge system, so we mostly ignored the it. Damn near ran out of fuel. had to "dead stick" it at Kawerau.
Turned out that the gauge was in fact telling me the truth. I had failed to ensure that the quickdrain had closed after refuelling at Whakatane...... had been leaking fuel for the whole flight.

Rob2
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#33
Dear James, to clarify several things . The efis used on certified helicopters and fixed wing have gone through tough testing and development to be as bullet proof as can be. Yes a lot of manufaturers do use them and there are varying levels of complexity between the different types.
There isn't a single certified piston heli that uses one. As a pilot that is flying this type of helicopter ( light, single seat, non ifr, limited range) you begin to realize that simplicity and reliability are most important.
The reason I don't like the digital lcd display as the primary indicator showing rotor/engine rpm, is that sunlight can make it almost impossible to read at times. Not only that, every pilot that has learned to fly heli is used to the dual needle mechanical or analog tach and only till you move up into the larger or IFR capable ships do we need to get familiar with the efis systems. as I said before those efis are nothing like the one being discussed for the mosi. You can waste time and money developing something that appeals to the person that doesn't yet have the experience and knowledge to understand why it should be kept simple . I know if and when I build a mosi,it will be kept as simple as can be and will always tell others this to.
Oh. And yes I do know the dif between a digital instrument and a analog one , i ment digital as in the sense of the LCD display, not in how the info is derived and processed .
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#34
Here is a cartoon of the Brantly's Low Fuel Warning System. This system is "Butt-Simple" and a Mosquito could be equipped this way, very easily.
It is reliable, positively calibrated, and almost 100% reliable.
The positive pressure inside the MZ-202 shroud at operating RPM is more than adequate to make the system operate.

On my helicopter, TEE "B" was at the 2 gallon level or about 11 minutes flight time. At the 18 minute level, the red light would come on occasionally as I maneuvered normally. At the 14 minute level, the light would be illuminated about 50% of the time unless it was dead calm and I was straight and level. As I approached 11 minutes the ratio of time ON vs. OFF would increase until at 2 gallons the light would remain on constantly.

I calibrated the height of TEE "B" with 2 normal size folks in cruise. I could have made it activate at 3 gallons, or 2 gallons, or whatever. Since most of my flying was around Atlanta and within 5 minutes of fuel, I used 2 gallons.



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#35
Rob Hall - 5/27/2011 8:02 AM

Ron,

Not too keen on the "watch the clock " idea.
Rob2

Oh No! I'm not Rob2 anymore? Got demoted? What am I going to tell Carrie?

Rob1, I think you've been Rob1 and I've been Rob2 for a while now, but if you want to
change, just let me know Wink I figured that since Texas was 4 times larger than Australia, I'd at least let you have the #1 position! Wink
Rob2 (or Rob1, heck I don't care Wink .
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#36
That's a nice one- did you ever notice if fuel dribbled out the static port when tanks were full? You wouldn't know unless someone was looking as you ran rpm's up to 100%. I wonder if it was a lower pressure switch than 2 or 3 psi. But it's nice and simple .
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#37
vortexring - 5/27/2011 10:28 AM

Dear James, to clarify several things . The efis used on certified helicopters and fixed wing have gone through tough testing and development to be as bullet proof as can be. Yes a lot of manufaturers do use them and there are varying levels of complexity between the different types.
There isn't a single certified piston heli that uses one. As a pilot that is flying this type of helicopter ( light, single seat, non ifr, limited range) you begin to realize that simplicity and reliability are most important.

I do believe simplicity and reliability are important. That is why the system is not already in it's flight testing.
Simplicity is based on what you think is simple. We have spent a large amount of time designing something that is way beyond being easy to understand. It's as close to a dual rotor/engine tach as you are going to get, with some huge benefits, which the analog needle gauges will not do. (split warning, low rotor speed warning, + others which I'm not going to list here).


vortexring

The reason I don't like the digital lcd display as the primary indicator showing rotor/engine rpm, is that sunlight can make it almost impossible to read at times.

That is a good point. It is another reason our system is not color. I have personally spent thousands of hours looking at different displays to find the right one. The one we are designing with is the only one I found that is easily sunlight readable. Glare can cause wash out, but any gauge will have the same effect with glare. Otherwise the display is fully readable. That killed the first system altogether....and why we went with a monochrome transflective display.

vortexring

Not only that, every pilot that has learned to fly heli is used to the dual needle mechanical or analog tach and only till you move up into the larger or IFR capable ships do we need to get familiar with the efis systems. as I said before those efis are nothing like the one being discussed for the mosi. You can waste time and money developing something that appeals to the person that doesn't yet have the experience and knowledge to understand why it should be kept simple . I know if and when I build a mosi,it will be kept as simple as can be and will always tell others this to.
Oh. And yes I do know the dif between a digital instrument and a analog one , i ment digital as in the sense of the LCD display, not in how the info is derived and processed .


Simple is what we are aiming at. Ask someone with a true EFIS.....they are not simple at all. Our design is aimed at simple. It is very intuitive, easily readable, and does other things the analog gauges can not do. Also, it will save a lot of weight compared to the separate gauges.

Simple is nice, but I feel safety is paramount. The system we are working on will give a number of additional safety features, which the typical analog type gauges will not. I'm not knocking the old style, I just think improvements can be made.

We are also taking the right steps to insure the system will perform the way it is intended. We have a test pilot who is qualified to do the flight testing. We will not move forward until he is happy with the units performance. He is a member here, but we will not disclose that information at this point.

You may change your mind once you see the full operation of the system at an airshow or other situation. You can't realize how much time we have spent making sure your concerns have been addressed, for they are mine as well.

But if I could sell you a system which is reliable, positively sunlight readable, simple, weighs less and provides more safety features than the analog, would you consider it? I think you would....... especially if the system is comparable in price to that group of separate analog gauges. It also includes gauges which are not in the standard instrument group (fuel, flight time, battery voltage, annunciator panel, ignition failure) , another nice feature.

It is our goal......and why it is taking so long.

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#38
The static port was on the longitudinal c/l of the helicopter. The top of the fuel tank was several inches lower than the port. I never had any of the residue of avgas around my static outlet.
I cannot remember what pressure the Dwyer switch was set at but I remember calibrating it using a coke bottle with water in it per the maintenance manual.

The pressure line was a 1/4" aluminum tube protruding into the oil cooler box where the engine cooling fans forced air out through the oil cooler. Cooling fan air also exited through a 6" x 18" rectangular hole on each side of the fuselage. The two cooling fans created a tremendous amount of flow and pressurized the engine compartment with enough pressure that if you didn't latch the little door for checking oil level, the air would pop it open.

It had to be 5+ PSI!
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#39
I looked up the Dwyer switch and it is for a 4" to 20" water column. That's 0.144 to 0.722 PSI. Surprisingly low.
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#40
rhrocker - 5/28/2011 3:05 AM

Rob Hall - 5/27/2011 8:02 AM

Ron,

Not too keen on the "watch the clock " idea.
Rob2

Oh No! I'm not Rob2 anymore? Got demoted? What am I going to tell Carrie?

Rob1, I think you've been Rob1 and I've been Rob2 for a while now, but if you want to
change, just let me know I figured that since Texas was 4 times larger than Australia, I'd at least let you have the #1 position!
Rob2 (or Rob1, heck I don't care .

OOOPS My slipup! Apologies....
Rob 1
Oh and as for the size ofTexas . I'll just let that one slide_________
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