Only if it needs to know its own location. As a means of scanning ahead and using the Imaging for a display, there is no need for the gyro.It, like you, must have some sort of reference to the horizon. Usually a laser ring gyro that is set while you are on the ground.
As a student pilot, my instructor told me if I got caught above a cloud layer, trim for approach speed and decent on a 180 degree heading, sit on your hands, and keep the heading with the rudder until you break out the bottom. Compass is most sensitive at the 180 degree heading.
The needle is most sensitive at 180 degrees and least at 360 degrees.I don't know why it should be more sensitive, but flying 180° (or 360°) eliminates the turning and acceleration errors that are more significant on an E-W heading.
Of course if you know there's enough ceiling below the cloud and your airplane is capable, you can just spin down through it. I had to do that once.
To the OP, if you want a cheap attitude indicator, buy or build a Stratux with AHRS and hook it up to Avare on your phone. Avare's PFD screen takes the info from the AHRS.
Turning errors are a maximum on a 180 or 360 heading.I don't know why it should be more sensitive, but flying 180° (or 360°) eliminates [wrong - see below] the turning and acceleration errors that are more significant on an E-W heading.
Hmmm, you're right and I was wrong (been a long time since ground school, and almost as long since I used a compass as anything other than a cross check to pilotage). Had to go back and visualize the angles, now I see what Pops meant about "more sensitive"Turning errors are a maximum on a 180 or 360 heading...
Flying a heading of 180 degrees in the Northern Hemisphere maximizes the turning error to the pilots advantage. The turning error shows a much larger turn than the aircraft actually makes.
I quit instructing 15 years ago when the maintenance duties became too much. I still taught the Aircraft Systems course in the college, though, until I left in 2011. Taught it for about 12 years, and covered gyro operations in every semester I taught it. I had attitude and heading indicators, turn coordinators and turn-and-bank instruments all opened up so one could see the operation of the stuff inside them, including the pendulum vanes in the attitude indicator that are fooled by a sustained turn. The attitude indicator has no sense of direction whatsoever, and the FAA's example of a 180-degree turn is an example of a turn sustained just long enough to see the effect of it on those vanes, causing the instrument to read a bit off once you straighten out. A rate-one turn takes one minute to make that 180-degree turn. A steeper turn takes less time but the turn's centrifugal forces are larger and can still get the gyro case tilted somewhat. Continuing the turn to 360 degrees cannot fix it. Turning the opposite direction will pull it back, but by the time you've done that you may as well have just flown straight for a minute and the thing would have fixed itself anyway.Yes, and I do not profess to know it all and that is why I said, "If i remember correctly....."
The older versions of the Instrument FlyingHandbook((FAA H--8083-15B) had more details on the operation of the self-erecting mechanism and the errors. If you need more information I can see if I can find my old copy that gave more detail on the errors. You could with your background study the system and see for yourself why the error cancels out in a 360 degree turn. If you want to check it out in flight you need a fast airplane. It is difficult to see the error in any turn slower than 350 knots.
Page 5-19 The Attitude Indicator
"There is also a possibility of a small bank angle
and pitch error after a 180° turn. These inherent errors are
small and correct themselves within a minute or so after
returning to straight-and-level flight."
I would like to hear your comments on the following. Are you currently teaching as a CFII?
You had a good CFI. Every pilot should know this but most do not. I try to spread the word but it is hard to teach those who already know it all.
You didn't get enough aviation weather. Maybe not recent stuff either.In a way, you're both correct and incorrect. I'm looking for a solution to problems I've encountered, regardless, and, yes I HAVE had aviation weather. Been a while and I could use a refresher course, but no prediction is ever 100% accurate. Pop-up storms happen.
Not legal for IFR, but in an emergency, Stratus or Stratux has ADHR and drives a display with all the bells and whistles. Stratus hooks to iPad/iPhone and ForeFlight. Stratux hooks to many Electronic Flight Bag software, IOS or Android, with Avare being freeware that runs on both platforms. The display can be adjusted to give in-flight traffic, weather, airport weather, etc. It can be a big help on X-Country flight.Thank you. I have never heard of Stratux, or the Avare app.
This is off the thread topic but I think it is important to present conflicting opinions to possibly correct the record. I am not alone in my opinion.Rent an airplane with a full panel and go play with it and see if a 360-degree turn leaves no error like a 180-degree turn does. You won't find it. Both will leave the error, and the 360-degree turn will leave a bigger error.
There is no substitute for training and knowledge but if you are scud running and know what you are doing it is much safer in an Ultra Light than in a faster, cleaner airplane. One mile clear of clouds at 300 feet AGL is much safer and more legal in an ultralight than it is in a Bonanza. Let's tell it like it is.I am with the other folks. Part 103 operators should avoid IMC like it will kill you right now, because it will. Tangling with Instrument Meteorological Conditions without a bunch of training and practice typically turns into Loss of Control in less than a minute. If you are lucky, you pop out without losing the wings to overspeed, and you recover. If you are not lucky, maybe you can still deploy the ballistic parachute. There are speed and bank limits on the 'chute too.
Avare is Android only.Stratux hooks to many Electronic Flight Bag software, IOS or Android, with Avare being freeware that runs on both platforms.
When weather is on the edge, it's hard to predict exactly how it will go, or whether/when the precip will change from rain to snow or vice versa, but you can bet nobody was predicting good VFR weather that day.If weather was really so predictable, stuff like last years polar vortex/'Great Texas Snowpocalyse' would have had more advanced warnings to prevent the loss of life that occurred.
Quite true; you have a lot more time to think about things, and if it gets really bad you can land an ultralight almost anywhere. A PPG is unique, in that it is completely stable, let go of the brake handles and it stays upright whether climbing or descending.There is no substitute for training and knowledge but if you are scud running and know what you are doing it is much safer in an Ultra Light than in a faster, cleaner airplane. One mile clear of clouds at 300 feet AGL is much safer and more legal in an ultralight than it is in a Bonanza. Let's tell it like it is.
I want to know why you think a powered paraglider in a farmers field below 300 feet AGL with a mile visibility is a bad idea. The pilot can see obstacles three away minutes in any direction and their is no danger to IFR traffic.
If it's true, I cannot see how continuing the turn for another 180° would cancel out the errors. That attitude indicator has absolutely no sense of direction. None. Its gyro spins about a vertical axis, the same axis the airplane turns around, and so it only responds to roll and pitch. Those pendulous vanes pull to the outside of the turn, any coordinated or skidding turn, and cause error, and they don't have any sense of direction either. They only respond to centrifugal force and gravity. The longer they are displaced, the more error they induce."Errors in both pitch and bank indications occur during normal coordinated turns. These errors are caused by the movement of the pendulous vanes by centrifugal force, resulting in the precession of the gyro toward the inside of the turn. The error is greatest in a 180° steep turn. If, for example, a 180° steep turn is made to the right and the aircraft is rolled out to straight-and-level flight by visual references, the miniature aircraft will show a slight climb and turn to the left. This precession error, normally 3° to 5°, is quickly corrected by the erecting mechanism. At the end of a 360° turn, the precession induced during the first 180° is cancelled out by precession in the opposite direction during the second 180° of turn. The slight precession errors induced during the roll-out are corrected immediately by pendulous vane action."
Dan, please comment. Do you disagree with this source?
All true. But, (that infamous but) if you like you can design the machine to do better. Reference the paraglider discussion above.Fly VFR. Flights through anything but thin layers were found to destroy airplanes and kill people.
Aneroid airspeed and altimetery were around, but blind flight was made possible by Sperry building gyroscopic instruments for turn rate and heading, and attitude, adding them to the existing instruments. Instrument navigation was by compass, time and airspeed, until radio nav aids were invented still later.
One maneuver that is a pretty reliable way to descend through an undercast without gyroscopic instruments is to spin the airplane until it comes out the bottom of the clouds, then recover from the spin. If you know spins and know you have enough clear air under the clouds it can work. Story is it was used in The Great War both to evade an attacker and to get below a deck.
In the airmail days, they had needle, ball, and airspeed, but not precision approaches. If the clouds were low, fuel was low, and you got caught on top, you ran the ship out of fuel out in the country someplace, spun it, and abandoned it. You would come down under parachute, and the fuel less airplane would spin down and crunch nearby. You survived and the mailbags were retrieved from the wrecked airplane and continued their trip. Story is that Lindberg even did that.
The spin works because drag on the airplane is huge and gravity is straight down, so all velocity except straight down goes away and bird spins down at low airspeed. Fast enough to kill you if you are still on board, but slow enough that airmail bags survive. And usually no fire because the fuel is gone and the engine is cold by the time of the crunch.
And if you would like to make Henryk happy fly a Kasper wing and there is no need to do that stall spin thingy thru the undercast. Just park in a vertical mush and if you see the ground land. If you don't see the ground brace for the crash because you are going to land anyway.Quite true; you have a lot more time to think about things, and if it gets really bad you can land an ultralight almost anywhere. A PPG is unique, in that it is completely stable, let go of the brake handles and it stays upright whether climbing or descending.
There is a difference between predicting the aviation weather for the next 12 to 24 hours and the weather for the next ten days. Big difference. Texas' weather problems would have been known to be approaching for days before the systems all froze up, but Texans don't know what real cold is, and the power and natural gas systems were never designed for the cold and ice like the same types of systems farther north are. There wouldn't have been much they could do about it in time anyway. I would hope that they've done some upgrading since then. It will happen again, maybe soon. The climate is cooling, and it's driven by minimum solar activity.If weather was really so predictable, stuff like last years polar vortex/'Great Texas Snowpocalyse' would have had more advanced warnings to prevent the loss of life that occurred. The Biden Administration seriously exacerbated things by shutting down natural gas fueled generation capacity (for 'green' reasons) at a crucial moment in time.
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