21st century instrumentation
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Attitude already comes from the IRS in aircraft so equipped. Gyro is only the backup (standby attitude).
Airspeed and Altitude must be referenced to the actual atmosphere being flown through. You're flying through air, not space. Spacial reversion is the backup already (BUSS/GPS).
The issue is recognising an instrumentation problem, and being able to ignore the suspect data and revert to backup source.
You're right though, some fresh thinking is probably useful!!
Airspeed and Altitude must be referenced to the actual atmosphere being flown through. You're flying through air, not space. Spacial reversion is the backup already (BUSS/GPS).
The issue is recognising an instrumentation problem, and being able to ignore the suspect data and revert to backup source.
You're right though, some fresh thinking is probably useful!!
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I have seen prototype units that use the Microsoft kinects pixel recognition system, and the iPad gyro chip. The kinects unit was especially hyperaccurate with true unbounded 360 spherical pixel recognition capability. It tested far more accurate and reliable than the laser gyros...
The units were being set up for underwater use, which has far greater needs than aviation due to lack of GPS update.
The units were being set up for underwater use, which has far greater needs than aviation due to lack of GPS update.
What perceived need are you purporting to address with this thread? As has been already mentioned, and should be abundantly clear, raw attitude information is available on all three sources in an airliner. Physically separating sensors in space does nothing for their sensitivity, nor their accuracy.
If you wish to pretend to be on the cutting edge of ergonomic thinking spend some time pondering how a modern stall warning should look and sound. And how mode reversion should be annunciated and summarised on an ECAM system. And how, for god's sakes, alpha can be intuitively displayed. Along with stall alpha corrected for altitude, mach number, mass and temperature.
While you are at it figure out how to get Airbus to permanently display flight path angle so that gamma can easily be ascertained.
If you wish to pretend to be on the cutting edge of ergonomic thinking spend some time pondering how a modern stall warning should look and sound. And how mode reversion should be annunciated and summarised on an ECAM system. And how, for god's sakes, alpha can be intuitively displayed. Along with stall alpha corrected for altitude, mach number, mass and temperature.
While you are at it figure out how to get Airbus to permanently display flight path angle so that gamma can easily be ascertained.
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Whenever I hear something like "we should convert to X because it's so much better than Y", I am reminded of what happened to Henry Ford.
He had to decide on what kind of engine to use for his new automobile. He had several choices, including electrical, steam, diesel and gasoline. Steam was discounted for inefficiency, electrical for battery capacity (still an issue), so it was down to diesel and gasoline (petrol).
Furthermore, he could choose between using petroleum diesel and bio-diesel, as both were available and usable at the time.
When looking at all the options, gasoline turned out to be best because
a) it was far cheaper than diesel (it was a by-product of making diesel)
b) it was far more available than bio-diesel (vegetable oil was harder to make in quantity at the time than diesel)
c) it cleaned up the environment because gasoline was being dumped as a waste product of making diesel.
So, the best solution at the time, cheaper and greener (using up all that waste gasoline) was to make his car use a gasoline engine.
Now, a hundred plus years later, it wasn't true, it's not cheaper, and it's certainly not greener.
Pitot tubes, vaccum gyros, pressure altimeters, and little balls in a curved tube of glass have been proven successful at giving the pilot sufficient information to keep the shiny side up, and continue to work if the electrical system stops working.
He had to decide on what kind of engine to use for his new automobile. He had several choices, including electrical, steam, diesel and gasoline. Steam was discounted for inefficiency, electrical for battery capacity (still an issue), so it was down to diesel and gasoline (petrol).
Furthermore, he could choose between using petroleum diesel and bio-diesel, as both were available and usable at the time.
When looking at all the options, gasoline turned out to be best because
a) it was far cheaper than diesel (it was a by-product of making diesel)
b) it was far more available than bio-diesel (vegetable oil was harder to make in quantity at the time than diesel)
c) it cleaned up the environment because gasoline was being dumped as a waste product of making diesel.
So, the best solution at the time, cheaper and greener (using up all that waste gasoline) was to make his car use a gasoline engine.
Now, a hundred plus years later, it wasn't true, it's not cheaper, and it's certainly not greener.
Pitot tubes, vaccum gyros, pressure altimeters, and little balls in a curved tube of glass have been proven successful at giving the pilot sufficient information to keep the shiny side up, and continue to work if the electrical system stops working.
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ENIAC worked. But that didnt stop us from designing better computers. 50 years ago not a soul envisaged you'd be reading your instruments off a a television whilst blind flying. I just think that with the pitot tubes out of the way life would be safer. They can be iced up, crushed by airbridges, blocked by insects or debris, damaged in many ways, easily and without such damage being very apparent.
Anyway I'm not trying to be smart here, just to throw ideas around, even if they do seem way out. Because the world of technology is improving at a pace where the exponent seems to be exponential itself and many new ideas outside of aviation could well benefit aviation very much if we heed them.
Imagine you were transported 50 years ahead in time. Not into a world where all modes of transport are unrecgnisable, just far enough that were still working with the same stuff, just improved, as we have improved upon the last 50 years.
Think of the jetliner docking at the terminal, raising its nose door and having the entire load of passengers withdrawn in their pod, a pallet which looks like and is in fact the inside of an airliner. Whilst refuelling takes place, a fresh pallet with new pre-boarded passengers, their baggage, clean toilets, full galleys is loaded and the aircraft is turned around in 15 minutes. Perhaps with a cargo pallet. Or a cargo half pallet and a passenger half pallet.
All clearances and comms via computer, no radio comms except with engineer. FMSs sort themselves out. No more computer to paper to computer via crew. Aircraft pushes itself back and is started automatically at optimum point. Aircraft displays taxi clearances, infrared cams see through fog.Separation much tighter, autopilots receive guidance from ATC systems, no more corridors and airways. Much better FCS (we're learning more about this right at this point with another loss of control accident in Air Asia) and foolproof instrumentation. Because if the computer fools the pilots as it does now, how can they be blamed for crashing?
Yes, I might be dreaming but thats what I intended this thread to be about... imagining the next state of the art.
Anyway I'm not trying to be smart here, just to throw ideas around, even if they do seem way out. Because the world of technology is improving at a pace where the exponent seems to be exponential itself and many new ideas outside of aviation could well benefit aviation very much if we heed them.
Imagine you were transported 50 years ahead in time. Not into a world where all modes of transport are unrecgnisable, just far enough that were still working with the same stuff, just improved, as we have improved upon the last 50 years.
Think of the jetliner docking at the terminal, raising its nose door and having the entire load of passengers withdrawn in their pod, a pallet which looks like and is in fact the inside of an airliner. Whilst refuelling takes place, a fresh pallet with new pre-boarded passengers, their baggage, clean toilets, full galleys is loaded and the aircraft is turned around in 15 minutes. Perhaps with a cargo pallet. Or a cargo half pallet and a passenger half pallet.
All clearances and comms via computer, no radio comms except with engineer. FMSs sort themselves out. No more computer to paper to computer via crew. Aircraft pushes itself back and is started automatically at optimum point. Aircraft displays taxi clearances, infrared cams see through fog.Separation much tighter, autopilots receive guidance from ATC systems, no more corridors and airways. Much better FCS (we're learning more about this right at this point with another loss of control accident in Air Asia) and foolproof instrumentation. Because if the computer fools the pilots as it does now, how can they be blamed for crashing?
Yes, I might be dreaming but thats what I intended this thread to be about... imagining the next state of the art.
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Yep, there are lots of ways to make improvements.
But until there's a sensor that can tell airspeed without using a pitot tube, you're going to need a pitot tube.
Airspeed and ground speed are not the same thing.
Knowing your ground speed is what non-pilots want to know, and pilots need for planning arrivals, descents, etc., but airspeed is needed for fuel flows, stall speeds, etc. (granted, the pitot tube method isn't perfectly accurate for stall speed, but we still don't have anything better, after a hundred years)
But until there's a sensor that can tell airspeed without using a pitot tube, you're going to need a pitot tube.
Airspeed and ground speed are not the same thing.
Knowing your ground speed is what non-pilots want to know, and pilots need for planning arrivals, descents, etc., but airspeed is needed for fuel flows, stall speeds, etc. (granted, the pitot tube method isn't perfectly accurate for stall speed, but we still don't have anything better, after a hundred years)
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I think having a high frequency sound transmitter in the nose of the aircraft and receivers in the wingtips and tail would work. Measure the frequency shift and you have the airspeed. Like a train whistle going past you..doppler effect. In effect, youre sending something (sound) into the medium youre flying through (air) and you're measuring its progress. Distance and absolute speed are known, time is calculated, airspeed can be derived?
Last edited by AfricanSkies; 20th Jan 2015 at 18:51.
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If you're referring to the Stall Warning cutting out while the IAS data was NCD and reappearing when nose-down was applied, then with respect it's fair to point out that a pilot who is well-versed in basic aerodynamics should know that said scenario indicates an issue with the Stall Warning system, because it is physically impossible to go from unstalled to stalled by reducing AoA. It's also worth pointing out that by the time the aircraft ended up in this state it was already too late to effect a recovery.
The problematic Thales AA model pitot tubes were already slated for replacement when the accident happened, and since they were replaced there has, to my knowledge, been no more incidents of triple pitot tube failure on the A330 or A340.
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Cut&Pasted from my posting in the AirAsia thread.
Old CFS dictum for Straight & Level 1 and subsequent flying lessons;
Select (attitude) Hold Adjust
Power (Thrust) Attitude Trim.
What is new in aviation when things are beginning to get out of hand, literally and figuratively? Or has this piece of basic flying training been edited out in favour of Magenta Children easyspeak?
Airbus may have its various Laws, but the Laws of Physics and Energy Management were applicable and immutable long before Alphonse and colleagues decided to make 'their' aircraft allegedly foolproof.
It is early days but if this accident resembles/mirrors/copies AF447, then what are the civil aviation training regimes doing/are going to do about the tendency for LOC at altitude, assuming AirAsia still had wings and stabiliser attached for the use of the crew??!!
I note a stunning lack of response, beyond one admission, to my request for reports from those who've actually handled their craft at high masses at max altitude.
Probably this specific topic belongs as a separate thread under Tech Log, but I'm still concerned at the lack of reports either way.
Tin hat donned in anticipation........................
Why are so many on this forum obsessed with new shiny hardware solutions which will not be fitted to ALL airframes til long after the next few high-altitude LOC accidents?
Old CFS dictum for Straight & Level 1 and subsequent flying lessons;
Select (attitude) Hold Adjust
Power (Thrust) Attitude Trim.
What is new in aviation when things are beginning to get out of hand, literally and figuratively? Or has this piece of basic flying training been edited out in favour of Magenta Children easyspeak?
Airbus may have its various Laws, but the Laws of Physics and Energy Management were applicable and immutable long before Alphonse and colleagues decided to make 'their' aircraft allegedly foolproof.
It is early days but if this accident resembles/mirrors/copies AF447, then what are the civil aviation training regimes doing/are going to do about the tendency for LOC at altitude, assuming AirAsia still had wings and stabiliser attached for the use of the crew??!!
I note a stunning lack of response, beyond one admission, to my request for reports from those who've actually handled their craft at high masses at max altitude.
Probably this specific topic belongs as a separate thread under Tech Log, but I'm still concerned at the lack of reports either way.
Tin hat donned in anticipation........................
Why are so many on this forum obsessed with new shiny hardware solutions which will not be fitted to ALL airframes til long after the next few high-altitude LOC accidents?
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The issue of GPS for attitude information usually comes up after an accident. While GPS is good, it isn't good enough to be used as an accurate source of attitude information.
GPS with IRU's mounted at 2 to 4 (nose and wing tip or all 4 points) points could be a great source of attitude information. When I say IRU I mean RLG and accelerometer updated by GPS, could be very accurate.
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Hey? What the hell ever happened to pitch and power? This accident and AF give me the feeling that the problem is culture and training. Thousands of hours sitting in a seat with otto the pilot connected to the FMS with no real issues have changed pilots from what they were 20 years ago. It gives me the thought that pilots spend more critical time during an abnormal event evaluating information and flipping through a QRH than simply reverting to pitch and power to drive through extreme circumstances. Is this not possible in the A320.330? I would expect that the PF should do this while the PNF rolls through procedure to evaluate all the warnings and QRH.
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grounded27,
I'm trying to make the same point but in different words, but I get the impression we are breaking wind in competition with thunder??!!
I don't know the status of most of the posters on this topic, a lot must be "simmers" or trolls or it depresses me seriously to think that some of the
posted is serious comment from experienced aircraft operators, who used to be known as pilots.
On my transition from military to civilian aviation 28 years ago, I recall being lambasted by the TC in the sim as I converted my brain from basic B&W artificial horizon instrument flying and was forced to slave myself to "the bars", even though I was FLYING the beast to the required accuracy. That type of TRTO conversion instruction is obviously not a new phenomenon, but fiddling with & following the APFDS system seemed to be an over-riding priority for that fleet chief trainer and others since then .
Others on these forums have and are calling for more BASIC flying as part of type conversion courses, but TCs have to follow whatever menu has been prescribed by the relevant xAA and Company.
Yet again a deafening silence from the AAs on this topic, presumably they need something like another few accidents and some media pressure before they will change their tune?
I'm trying to make the same point but in different words, but I get the impression we are breaking wind in competition with thunder??!!
I don't know the status of most of the posters on this topic, a lot must be "simmers" or trolls or it depresses me seriously to think that some of the
posted is serious comment from experienced aircraft operators, who used to be known as pilots.On my transition from military to civilian aviation 28 years ago, I recall being lambasted by the TC in the sim as I converted my brain from basic B&W artificial horizon instrument flying and was forced to slave myself to "the bars", even though I was FLYING the beast to the required accuracy. That type of TRTO conversion instruction is obviously not a new phenomenon, but fiddling with & following the APFDS system seemed to be an over-riding priority for that fleet chief trainer and others since then .
Others on these forums have and are calling for more BASIC flying as part of type conversion courses, but TCs have to follow whatever menu has been prescribed by the relevant xAA and Company.
Yet again a deafening silence from the AAs on this topic, presumably they need something like another few accidents and some media pressure before they will change their tune?
Is the world crying out for inertial sensors in aeroplane wingtips? No, not really - the ones we have in the fuselage work fine, thank you. Anyway, I don’t think they would add much to accuracy as the wing flex on large airliners would see them pointing all over the place in turbulence.
As others have said, attitude/position reference technology is mature and not in great need of improvement. What might be is the presentation to the pilot, which hasn’t changed much in commercial aviation since instruments were first built. But that’s another topic entirely.
Probably what has set off this discussion are recent incidents/accidents involving loss-of-control following errors in pitot/static/AoA sensing systems. Most aircraft this side of FBW military ones will fly quite happily without having to “know” what their airspeed is. Having a set of wings and a tailplane bolted to a fuselage in the conventional manner leads to an aeroplane that has enough static/dynamic stability to fly itself most of the time, like a well-made paper dart.
Once you start adding software protections against things like overspeed and stalling, you become vulnerable to sensor failures. Very, very rarely, the systems that for 99.9999% of the time do an exceedingly good job of keeping you safe and sound are now actively trying to kill you. No wonder it comes as a bit of a shock to many when this happens. Yes, there are memory drills for power and attitude that if executed in a timely and correct fashion will turn it into a non-event. The problem lies in actually diagnosing the issue(s) correctly in the first place and taking back control of the aircraft from the systems that are no longer performing their function correctly. As (bad) luck would have it, the most likely time these systems are going to freak out is not in a clear blue sky with an uninterrupted view of the ground but in the middle of a thunderstorm at night, where pilot workload is already high.
The 777/787 have a convenient switch just above the head of the captain. In an Airbus, you have to pull a selection of circuit breakers, so I’m told. The effect is to return these aircraft to something that relies on aerodynamics and basic controls to fly rather than computer augmentation. There are a further set of CBs to pull if you can’t get the myriad of warning systems, now working on false data, to shut up and let you think.
It’s a problem and it’s not going away. However, most agree that the day-to-day benefits of FBW far outweigh the ultra-rare occasions that it dumps you in the mire. Doesn’t mean that we shouldn’t be trying to solve the problem from all angles, though.
As others have said, attitude/position reference technology is mature and not in great need of improvement. What might be is the presentation to the pilot, which hasn’t changed much in commercial aviation since instruments were first built. But that’s another topic entirely.
Probably what has set off this discussion are recent incidents/accidents involving loss-of-control following errors in pitot/static/AoA sensing systems. Most aircraft this side of FBW military ones will fly quite happily without having to “know” what their airspeed is. Having a set of wings and a tailplane bolted to a fuselage in the conventional manner leads to an aeroplane that has enough static/dynamic stability to fly itself most of the time, like a well-made paper dart.
Once you start adding software protections against things like overspeed and stalling, you become vulnerable to sensor failures. Very, very rarely, the systems that for 99.9999% of the time do an exceedingly good job of keeping you safe and sound are now actively trying to kill you. No wonder it comes as a bit of a shock to many when this happens. Yes, there are memory drills for power and attitude that if executed in a timely and correct fashion will turn it into a non-event. The problem lies in actually diagnosing the issue(s) correctly in the first place and taking back control of the aircraft from the systems that are no longer performing their function correctly. As (bad) luck would have it, the most likely time these systems are going to freak out is not in a clear blue sky with an uninterrupted view of the ground but in the middle of a thunderstorm at night, where pilot workload is already high.
The 777/787 have a convenient switch just above the head of the captain. In an Airbus, you have to pull a selection of circuit breakers, so I’m told. The effect is to return these aircraft to something that relies on aerodynamics and basic controls to fly rather than computer augmentation. There are a further set of CBs to pull if you can’t get the myriad of warning systems, now working on false data, to shut up and let you think.
It’s a problem and it’s not going away. However, most agree that the day-to-day benefits of FBW far outweigh the ultra-rare occasions that it dumps you in the mire. Doesn’t mean that we shouldn’t be trying to solve the problem from all angles, though.
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"BARKINGMAD and grounded27, attitude information already comes from the IRS!"
I believe I was aware that after a few years on INS/IRS equipped aircraft that this is indeed the case.
So your point is?
I believe I was aware that after a few years on INS/IRS equipped aircraft that this is indeed the case.
So your point is?
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A note about GPS attitude.
It is perfectly possible & cheap to determine attitude from multiple GPS sensors. It doesn't depend on absolute position in space but on the different phase of a single GPS signal, as received by two or more sensors about 5 to 10 cm apart. They don't know precisely where they are relative to the earth, but they do know position relative to each other. Using this technique, cargo ships for example can generate a true heading accurate to about a fifth of a degree.
The reason it hasn't taken the aviation world by storm is partly due to continuity & availability of signal, and partly due to the lack of a signal when you're inverted!
None of this improves the recent LOC accidents, as every airliner is well served with accurate & very expensive redundant RLGs for perfect attitude sensing. Whether the pilots can use attitude intelligently is not a given....
It is perfectly possible & cheap to determine attitude from multiple GPS sensors. It doesn't depend on absolute position in space but on the different phase of a single GPS signal, as received by two or more sensors about 5 to 10 cm apart. They don't know precisely where they are relative to the earth, but they do know position relative to each other. Using this technique, cargo ships for example can generate a true heading accurate to about a fifth of a degree.
The reason it hasn't taken the aviation world by storm is partly due to continuity & availability of signal, and partly due to the lack of a signal when you're inverted!
None of this improves the recent LOC accidents, as every airliner is well served with accurate & very expensive redundant RLGs for perfect attitude sensing. Whether the pilots can use attitude intelligently is not a given....
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Not a very good idea, sorry
I think having a high frequency sound transmitter in the nose of the aircraft and receivers in the wingtips and tail would work. Measure the frequency shift and you have the airspeed. Like a train whistle going past you..doppler effect. In effect, youre sending something (sound) into the medium youre flying through (air) and you're measuring its progress. Distance and absolute speed are known, time is calculated, airspeed can be derived?
Perhaps you mean some kind of device that emits "pings" and you measure the time they need to arrive at the receiver? But that would require the speed of sound to depend on the speed of the medium, which it doesn't. It doesn't depend on the speed of the source - otherwise you wouldn't get a sonic boom - so it also can't depend on the speed of the medium.