DI, AI, and balance ball all not working properly...Why???
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Can you just clarify Whirly was it a Interior trim or where you talking about the trim wheel not being set neutral?
And to be honest I wouldn't have been bothered flying it VFR either if required for a positioning flight / test flight. I wouldn't except it for teaching though.
The vacum pressure indications really depend on where the leak is, where the suction gauge is and how good the pump is.
You can get sub normal rpms while still showing good suction.
I have had this and the only way i could tell was the DI felt soft when adjusting it.
MJ
And to be honest I wouldn't have been bothered flying it VFR either if required for a positioning flight / test flight. I wouldn't except it for teaching though.
The vacum pressure indications really depend on where the leak is, where the suction gauge is and how good the pump is.
You can get sub normal rpms while still showing good suction.
I have had this and the only way i could tell was the DI felt soft when adjusting it.
MJ
assuming you do the same amount of work as me is admitting that you generally do ****** all!!!!
Well, offering an opinion now, the aircraft shifted on the ground, and the trim (which I understand to be the cockpit surround, nothing to do with pitch control) indicates that something's moved in that area.
Combining the normally reading ASI and Altimeter, with the poorly reading DI and AI, along with the knowledge that pitot-static hose is generally less stiff than vacuum system hose, suggests to me that the stiffer vacuum system hose, rather than the (usually) more flexible pitot-static hose (or possibly it's connections) has become damaged during it's shifting causing a partial or eratic loss of vacuum.
The damage must presumably be between the off-take for the vacuum indicator and the actual gyro instruments, since if it was nearer the vacuum pump then it would show as a suction failure. My best guess is that it's probably at the nipples on the reverse of either the DI or AI.
You've mentioned by the way that the AI has never been brilliant - it could be that this was the final straw in a progressive failure?
The slip ball, in my opinion, is probably the most difficult - a vacuum failure when flying VMC should be nothing more than an irritation once it's identified. The fact that somebody who knows the aircraft identifies no handling oddities, combined with the ball being similarly out on the ground would seem to eliminate a bent airframe (which if it's undercarriage would only show on the ground, and if it's wing would only show in the air - and both being bent to show the same errors without distortion being visible or any handling problems seems outside the realms of reasonable possibility). There is no external input into the slip-ball which can be distrupted. The instrument panel in a C150 is wall-to-wall so enough distortion to move a normal slip-ball out that much would, in my opinion, be readily visible.
So, my best guess is that the slip-ball has become damaged somewhere out of sight. If the case, this is probably the only thing to endanger the aircraft for VFR flight - not because it's an essential instrument, but because a fluid leak into the cockpit can potentially cause incapacitation.
So, my suggestion, following on from Airbedane's, is to have an instrument fitter remove the instrument panel and check all of the instrument connections (note ALL, something else may have worked loose but not shown itself yet), along with serviceability and alignment of the slip ball.
But, I would also have an LAME do a rigging check to be on the safe side - forces large enough to shift a large concrete block via the tie-down point may potentially have bent something that you don't know about yet. To be frank, at the wing/strut tiedown point on a C150 I think that it's unlikely, but it does no harm to check whilst it's in the hangar.
G
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because a fluid leak into the cockpit can potentially cause incapacitation.
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How about-
(1) "Trim" (instrument panel surround) shifted because someone held onto it while pulling their seat forward
(2) Vacuum system failure which caused DI/AI problems
(3) Apparent problems with the balance ball caused by (i) flying in such a way as to compensate for the DI/turn indications, (ii) flying a fixed wing like a helicopter (ie too much on the feet) and (iii) flying on the compass rather than on the DI
(1) "Trim" (instrument panel surround) shifted because someone held onto it while pulling their seat forward
(2) Vacuum system failure which caused DI/AI problems
(3) Apparent problems with the balance ball caused by (i) flying in such a way as to compensate for the DI/turn indications, (ii) flying a fixed wing like a helicopter (ie too much on the feet) and (iii) flying on the compass rather than on the DI
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The balance ball was out on the ground though.....
Could this be linked to the instrument rotating a few degrees in the panel, or the panel shifting slightly?
BoeingMEL, you should know (as a former professional pilot) that the minimum instrumentation for day VFR flight in a C152 is:-
ASI
ALT
Magnetic compass
Tacho
oil pressure guage
oil temp guage
fuel guage
Doesn't mention anything about any gyroscopic instrumentation.
EA
Could this be linked to the instrument rotating a few degrees in the panel, or the panel shifting slightly?
BoeingMEL, you should know (as a former professional pilot) that the minimum instrumentation for day VFR flight in a C152 is:-
ASI
ALT
Magnetic compass
Tacho
oil pressure guage
oil temp guage
fuel guage
Doesn't mention anything about any gyroscopic instrumentation.
EA
The Original Whirly
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To clarify...I was indeed talking about the instrument panel surround, not the trim wheel, which was just fine. Apologies for the ambiguity. I was tired, couldn't think of correct terminology, and didn't realise it was confusing.
Genghis,
Very helpful post. "Poorly reading" is the most accurate description for the AI and DI; neither had actually failed completely. So a partial loss of vaccuum makes sense.
I couldn't have explained it in that much detail and that eloquently, but that was why I couldn't make any sense out of it. The ball was well over to the left, both on the ground and in the air. And the handling was definitely normal - believe me, with that many things going wrong, I was ready for anything, and checking everything at very frequent intervals. I too am wondering why a fluid leak into the cockpit should cause incapacitation, so please explain.
Tee,
Are you deliberately trying to wind me up? Because if so, you're going the right way about it.
1) Only two of us in the group, I'm the one who pulls the seat forward, and I don't hold on to the panel surround while doing so. OK, you weren't to know who flies the aircraft.
2) Agreed.
3) (i)The balance ball had identical problems while taxiing. I wasn't flying to compensate for the DI/turn indications; I was looking out the window and using the compass for...what it's there for! I don't find a lack of DI and AI a major problem requiring any change in the way I fly, merely an irritation.
(ii) Actually, in a helicopter you hardly use the pedals in the air, only while climbing, descending, or especially while hovering. And I DON'T fly a C150 like a helicopter!!!!! And like I said, in very light wind, she was flying beautifully hands (and feet) off. (iii) There is absolutely nothing wrong with flying on the compass rather than the DI in VMC. As I said, I do it frequently, so that I can keep looking outside rather than at the instrument panel. It really worries me if people think using the compass for navigation is something odd, difficult, or likely to cause errors; it isn't. In some ways I actually prefer a nav instrument that I don't have to keep adjusting...though if I have a working DI I do set it and tend to use both of them. If PPLs are ending up thinking using the compass for what it's designed for is somehow odd, I can think of some criticisms to be levelled at other instructors!!!
Anyway, we'll definitely get things checked out before she's flown again. Thanks people.
Genghis,
Very helpful post. "Poorly reading" is the most accurate description for the AI and DI; neither had actually failed completely. So a partial loss of vaccuum makes sense.
The slip ball, in my opinion, is probably the most difficult - a vacuum failure when flying VMC should be nothing more than an irritation once it's identified. The fact that somebody who knows the aircraft identifies no handling oddities, combined with the ball being similarly out on the ground would seem to eliminate a bent airframe (which if it's undercarriage would only show on the ground, and if it's wing would only show in the air - and both being bent to show the same errors without distortion being visible or any handling problems seems outside the realms of reasonable possibility). There is no external input into the slip-ball which can be distrupted. The instrument panel in a C150 is wall-to-wall so enough distortion to move a normal slip-ball out that much would, in my opinion, be readily visible.
Tee,
How about-
(1) "Trim" (instrument panel surround) shifted because someone held onto it while pulling their seat forward
(2) Vacuum system failure which caused DI/AI problems
(3) Apparent problems with the balance ball caused by (i) flying in such a way as to compensate for the DI/turn indications, (ii) flying a fixed wing like a helicopter (ie too much on the feet) and (iii) flying on the compass rather than on the DI
(1) "Trim" (instrument panel surround) shifted because someone held onto it while pulling their seat forward
(2) Vacuum system failure which caused DI/AI problems
(3) Apparent problems with the balance ball caused by (i) flying in such a way as to compensate for the DI/turn indications, (ii) flying a fixed wing like a helicopter (ie too much on the feet) and (iii) flying on the compass rather than on the DI
1) Only two of us in the group, I'm the one who pulls the seat forward, and I don't hold on to the panel surround while doing so. OK, you weren't to know who flies the aircraft.
2) Agreed.
3) (i)The balance ball had identical problems while taxiing. I wasn't flying to compensate for the DI/turn indications; I was looking out the window and using the compass for...what it's there for! I don't find a lack of DI and AI a major problem requiring any change in the way I fly, merely an irritation.
(ii) Actually, in a helicopter you hardly use the pedals in the air, only while climbing, descending, or especially while hovering. And I DON'T fly a C150 like a helicopter!!!!! And like I said, in very light wind, she was flying beautifully hands (and feet) off. (iii) There is absolutely nothing wrong with flying on the compass rather than the DI in VMC. As I said, I do it frequently, so that I can keep looking outside rather than at the instrument panel. It really worries me if people think using the compass for navigation is something odd, difficult, or likely to cause errors; it isn't. In some ways I actually prefer a nav instrument that I don't have to keep adjusting...though if I have a working DI I do set it and tend to use both of them. If PPLs are ending up thinking using the compass for what it's designed for is somehow odd, I can think of some criticisms to be levelled at other instructors!!!
Anyway, we'll definitely get things checked out before she's flown again. Thanks people.
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Boeing MEL - what b
s!
Having had (yesterday) a complete vacuum failure half way along the first leg of a 3 part cross-country then I have to ask - what's the problem? (and this was San Francisco - Long Beach via two intermediate stops, not some little UK tootle). Weather was VMC on top during the failure with a a VFR approach, the subsequent ones were flown VFR. Flew the aircraft by compass, turn and slip, and VOR (Seneca in this case). The most important piece of eqpt. required was the 'post-its' to cover up the faulty pair!
Maybe your comments underly a personal worry that partial panel would be too difficult?
Whirly
Can't add anything different to what others have said. However, I would re-iterate checking the mounting of the turn co-ord (a la EA's answer). If the aircraft trims straight and level still then it's probably just this coupled with suction problems.
s!Having had (yesterday) a complete vacuum failure half way along the first leg of a 3 part cross-country then I have to ask - what's the problem? (and this was San Francisco - Long Beach via two intermediate stops, not some little UK tootle). Weather was VMC on top during the failure with a a VFR approach, the subsequent ones were flown VFR. Flew the aircraft by compass, turn and slip, and VOR (Seneca in this case). The most important piece of eqpt. required was the 'post-its' to cover up the faulty pair!
Maybe your comments underly a personal worry that partial panel would be too difficult?
Whirly
Can't add anything different to what others have said. However, I would re-iterate checking the mounting of the turn co-ord (a la EA's answer). If the aircraft trims straight and level still then it's probably just this coupled with suction problems.
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Whirly, post whenever you like. The adults can handle it.
If the vacuum gauge (not guage) is showing around 5, then there's no leak. It's more likely to be blocked or "old" filters, or (less likely) kinked tubes to the instrument that's messing around.
Be interested to know the diagnosis (if there is one, rather than lots of messing around behind the panel, during which the problem miraculously disappears).
If the vacuum gauge (not guage) is showing around 5, then there's no leak. It's more likely to be blocked or "old" filters, or (less likely) kinked tubes to the instrument that's messing around.
Be interested to know the diagnosis (if there is one, rather than lots of messing around behind the panel, during which the problem miraculously disappears).
The following is taken verbatim from the Winter 2000 issue of CHIRP GA feedback, which is online at http://www.chirp.co.uk/new/Aviation/IndexAir.html
I know of no particular differences between the fluids in compasses and slip-balls, and hopefully justifies my comments about incapacitation.
G
Pilot Incapacitation
Reported occurrences of pilot incapacitation in General Aviation are relatively rare, but that does not mean that the problem does not exist. Incapacitation can result from several causes and may have extremely serious consequences in a single-pilot operation, particularly if the problem is not recognised at an early stage. The following report describes the insidious nature of some forms of contamination and the benefit in taking prompt action.
I collected our group PA32 from the Midlands on a Spring morning in 1994 for a day trip, with my wife and small children, to visit relations near the South Coast. On checking the aircraft I examined the 'snag' sheet, which was used to detail any known faults/comments noted by previous pilots and still outstanding. A 'snag' had been noted that stated that the compass fluid was leaking. Inspection of the compass (top centre on the windscreen) showed a small bubble at the top. Conditions were good VMC, the VORs all worked correctly, I was familiar with the route and I also carried a small hand compass in my flight bag. I could check the Direction Indicator against the runway heading prior to departure and with the aid of VORs in flight, so I was quite happy to go ahead.
On climb out I did notice that a prolonged trickle of fluid ran from the compass onto the carpet just in front, and between, the pilot and front passenger seat. I thought nothing more of it. After about 20 minutes my wife complained of feeling sick - very unusual, as she has never experienced airsickness. However, it was a little bumpy so, again, I was not unduly concerned - although I did register the fact that the compass fluid did produce quite a strong smell. A few minutes later she was clearly in some discomfort, shortly followed by a complaint that she was losing the feeling in her legs. She does suffer from mild asthma and it then struck me that she could be suffering from the affect of the smell of the fluid leaking from the compass. I felt fine but, as a precaution, I immediately adjusted all the available fresh air direct to my face. I then diverted to the nearest available airfield and executed what I thought to be a perfect landing just 10 minutes later - only to be told as I turned off the grass runway that I had landed "off the runway". I had, in fact, not noticed that the runway markers had recently been moved and, instead of landing between the markers, I had landed on the nicely cut strip to the right of the right side markers. I still felt fine - although slightly embarrassed!
On explaining my predicament as I taxied to park the aircraft, the airfield could not have been more helpful, instructing me to immediately shut down. They entertained my children, provided first aid for my wife who rapidly recovered in the fresh air, and removed the compass, which we carried home in the external locker - all without charge or landing fee! After an hour or so we completed our journey.
It may be just as well that my wife's asthma probably caused her to be more sensitive to the smell giving me advance warning of the problem - the prospect of heading west on autopilot whilst slowly losing one's judgement does not bear thinking about! I certainly do not recall any aspect of my training (including commercial balloon pilot exams.) that warned of the dangers of noxious fumes from a leaking compass!
I know of no particular differences between the fluids in compasses and slip-balls, and hopefully justifies my comments about incapacitation.
G
Pilot Incapacitation
Reported occurrences of pilot incapacitation in General Aviation are relatively rare, but that does not mean that the problem does not exist. Incapacitation can result from several causes and may have extremely serious consequences in a single-pilot operation, particularly if the problem is not recognised at an early stage. The following report describes the insidious nature of some forms of contamination and the benefit in taking prompt action.
I collected our group PA32 from the Midlands on a Spring morning in 1994 for a day trip, with my wife and small children, to visit relations near the South Coast. On checking the aircraft I examined the 'snag' sheet, which was used to detail any known faults/comments noted by previous pilots and still outstanding. A 'snag' had been noted that stated that the compass fluid was leaking. Inspection of the compass (top centre on the windscreen) showed a small bubble at the top. Conditions were good VMC, the VORs all worked correctly, I was familiar with the route and I also carried a small hand compass in my flight bag. I could check the Direction Indicator against the runway heading prior to departure and with the aid of VORs in flight, so I was quite happy to go ahead.
On climb out I did notice that a prolonged trickle of fluid ran from the compass onto the carpet just in front, and between, the pilot and front passenger seat. I thought nothing more of it. After about 20 minutes my wife complained of feeling sick - very unusual, as she has never experienced airsickness. However, it was a little bumpy so, again, I was not unduly concerned - although I did register the fact that the compass fluid did produce quite a strong smell. A few minutes later she was clearly in some discomfort, shortly followed by a complaint that she was losing the feeling in her legs. She does suffer from mild asthma and it then struck me that she could be suffering from the affect of the smell of the fluid leaking from the compass. I felt fine but, as a precaution, I immediately adjusted all the available fresh air direct to my face. I then diverted to the nearest available airfield and executed what I thought to be a perfect landing just 10 minutes later - only to be told as I turned off the grass runway that I had landed "off the runway". I had, in fact, not noticed that the runway markers had recently been moved and, instead of landing between the markers, I had landed on the nicely cut strip to the right of the right side markers. I still felt fine - although slightly embarrassed!
On explaining my predicament as I taxied to park the aircraft, the airfield could not have been more helpful, instructing me to immediately shut down. They entertained my children, provided first aid for my wife who rapidly recovered in the fresh air, and removed the compass, which we carried home in the external locker - all without charge or landing fee! After an hour or so we completed our journey.
It may be just as well that my wife's asthma probably caused her to be more sensitive to the smell giving me advance warning of the problem - the prospect of heading west on autopilot whilst slowly losing one's judgement does not bear thinking about! I certainly do not recall any aspect of my training (including commercial balloon pilot exams.) that warned of the dangers of noxious fumes from a leaking compass!
The Original Whirly
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Just been talking to the other group member, now back after Easter. Aircraft will hopefully be looked at in the next couple of days. I'll let you know the diagnosis.
We're also looking for a better place to tie her down.
I'll continue to post, tired or not. Of course I will - I'm a PPRuNe addict. Most people seem to understand what I say. the others will just have to put up with it...or not bother reading.
Again, thanks for all the useful comments.
We're also looking for a better place to tie her down.
I'll continue to post, tired or not. Of course I will - I'm a PPRuNe addict. Most people seem to understand what I say. the others will just have to put up with it...or not bother reading.
Again, thanks for all the useful comments.
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Oh Dear!
Mmmm a bit of a hornet's nest here methinks! I make just 2 more points here and will then retire with a cold beer.
1: Airmanship encompasses more than the carriage of minimum equipment.
2: To suggest flying partial panel with all gyro-instruments out in VMC may not be a problem. Now try the same exercise if the vis deteriorates or with your windshield coated with several litres of hot engine oil.
In this old-timer's experience, the pilots who are sloppy about planning, preparation and safety are usually the ones who cant get close to +/- 50', 5 degrees or 10 knots..... cheers! bm
1: Airmanship encompasses more than the carriage of minimum equipment.
2: To suggest flying partial panel with all gyro-instruments out in VMC may not be a problem. Now try the same exercise if the vis deteriorates or with your windshield coated with several litres of hot engine oil.
In this old-timer's experience, the pilots who are sloppy about planning, preparation and safety are usually the ones who cant get close to +/- 50', 5 degrees or 10 knots..... cheers! bm
Last edited by BoeingMEL; 13th Apr 2004 at 09:44.
The Original Whirly
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Ah, BoeingMEL, I had a look at your profile. Fly the 737 and B206 do you? That explains it. You're used to lots of instruments. But to me, you see, this wasn't partial panel; it was what I'm used to anyway. Along with most pilots of cubs, austers, microlights, and a whole collection of other aircraft. The DI and AI were useful luxuries. Must admit though, non-working instruments are distracting; Chilli Monster's post-it notes would have been useful.
Deteriorating vis? I'd divert - loads of airfields on that route. I'd do that anyway, since I don't hold an IMC. Several litres of engine oil!!!! Possible but unlikely. OK, I admit it; I hadn't thought of that one!!!
Planning and preparation done in detail. Checks done, go/no go decision considered in detail. 50', 5 degrees, 10 knots...the limits for the CPL(H) flight test, which I passed on an R22, one of the most unstable flying machines there is...much much MUCH easier in a C150.
Hmmm...Whirly, he obviously isn't even discussing you; why are you even posting?
Deteriorating vis? I'd divert - loads of airfields on that route. I'd do that anyway, since I don't hold an IMC. Several litres of engine oil!!!! Possible but unlikely. OK, I admit it; I hadn't thought of that one!!!
Planning and preparation done in detail. Checks done, go/no go decision considered in detail. 50', 5 degrees, 10 knots...the limits for the CPL(H) flight test, which I passed on an R22, one of the most unstable flying machines there is...much much MUCH easier in a C150.
Hmmm...Whirly, he obviously isn't even discussing you; why are you even posting?
She's right you know Boeing.
There is nothing wrong with flying a simple slow aircraft like a C150 with a faulty vacuum system, nor without a serviceable slip-ball so long as you know that those are faulty, and nothing else is .
I've flown, quite legally and safely, aircraft who were equipped with an ASI, altimeter and compass, and nothing else (and two of those were not part of the MEL). They were, to be fair, types that maked a C150 look complex and high-performance, but they were still aeroplanes. Conversely, you'd not fly your 737 with the standard C150 instrument fit would you. It's all horses for courses.
I still stand by my concerns about a possible leaky slip-ball mind you, but it would appear from responses above that nobody else, however experienced, was aware of that PA32 report and it's near-nasty consequences - so if nobody else was, it's a little hard to criticise Whirly for lack of awareness on that point.
G
There is nothing wrong with flying a simple slow aircraft like a C150 with a faulty vacuum system, nor without a serviceable slip-ball so long as you know that those are faulty, and nothing else is .
I've flown, quite legally and safely, aircraft who were equipped with an ASI, altimeter and compass, and nothing else (and two of those were not part of the MEL). They were, to be fair, types that maked a C150 look complex and high-performance, but they were still aeroplanes. Conversely, you'd not fly your 737 with the standard C150 instrument fit would you. It's all horses for courses.
I still stand by my concerns about a possible leaky slip-ball mind you, but it would appear from responses above that nobody else, however experienced, was aware of that PA32 report and it's near-nasty consequences - so if nobody else was, it's a little hard to criticise Whirly for lack of awareness on that point.
G
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I have to say BoingMEL I agree with Whirly here. I also fly microlights as well as significantly bigger stuff and Rotary.
The microlights I fly have no gyroscopic instruments at all, in fact all they have is an altimeter, VSI, compass and RPM guage and so find your insinuation that a pilot who flies without them is sloppy a little offensive. I certainly find no problem with speed/height/heading during CPL/IR ops or flying an aircraft with minimal equipment VFR. There are also a lot of other Microlight and classic aircraft pilots out there who seem to back this up with safe flying?
Perhaps you have become too reliant on technology and this has clouded your view of the simpler things?
I had an an engine blow oil onto the windscreen in a microlight about 15 secs before it stopped. I put my head out the window and landed safely. No need for any gyro instruments there.
If you are in a 152, you have inadvertantly entered IMC and then the donk quits and blows oil over the screen it probably means your going to have a bad day. Not sure how a fulll set of gyros is going to help in that situation!!!
The microlights I fly have no gyroscopic instruments at all, in fact all they have is an altimeter, VSI, compass and RPM guage and so find your insinuation that a pilot who flies without them is sloppy a little offensive. I certainly find no problem with speed/height/heading during CPL/IR ops or flying an aircraft with minimal equipment VFR. There are also a lot of other Microlight and classic aircraft pilots out there who seem to back this up with safe flying?
Perhaps you have become too reliant on technology and this has clouded your view of the simpler things?
I had an an engine blow oil onto the windscreen in a microlight about 15 secs before it stopped. I put my head out the window and landed safely. No need for any gyro instruments there.
If you are in a 152, you have inadvertantly entered IMC and then the donk quits and blows oil over the screen it probably means your going to have a bad day. Not sure how a fulll set of gyros is going to help in that situation!!!
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Genghis - I know (well, third-hand) of two pilots who were recently made to feel very unwell by a leaking compass; like others here, I was surprised that it could have such an effect.
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OK you win (ish!)
Healthy debate and enjoyable too! These exchanges of opinion exercise the grey cells and do extend knowledge and understanding! Just to make clear though.... when "my" Bonanza dumped oil over the windshield, the donk didn't quit... the guage still showed 30 psi when I landed 15 minutes later (after an ILS approach to minimums and landing looking through the side window.) Secondly.... and I do believe this passionately: any PPL instructor can (and should!) learn about those instruments and be able to describe their operation clearly to students. Dear God.. there cant be more than 3 or 4 hours learning to cover them all! Kind regards to all bm
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Whirly, I have no idea what could cause the balance ball to fail, so I won't even try to add to the excellent-sounding answers from those who know!
But I will add to the debate about flying without these instruments. I agree with you - not a problem at all!
On my 170A flight for my CPL, I had a genuine vacuum failure. Was approaching a turning point on the navigation section of the flight when I glanced down at the instruments prior to making the turn. Was quite surprised to see the AI pointing off in some obscure direction. I checked the cockpit and quickly realised that I'd had a vacuum failure. My instructor was sitting there quietly, and although I wasn't aware of any way of disabling the vacuum system from inside the cockpit I suspected that this was an instructor-induced failure. I told my instructor what I was doing, made the turn on the compass, and expected the instructor to restore the vacuum, but no - this was a genuine failure.
We completed the flight without any further incidents. (The b@stard instructor still put me under the foggles for the diversion and had me do the entire instrument section of the flight partial-panel, too!) During the debrief, instructor told me that he'd noticed the failure a good 5 minutes or so before me. So it seems that it's quite possible to fly an aircraft without looking at the instruments after all
FFF
---------------
But I will add to the debate about flying without these instruments. I agree with you - not a problem at all!
On my 170A flight for my CPL, I had a genuine vacuum failure. Was approaching a turning point on the navigation section of the flight when I glanced down at the instruments prior to making the turn. Was quite surprised to see the AI pointing off in some obscure direction. I checked the cockpit and quickly realised that I'd had a vacuum failure. My instructor was sitting there quietly, and although I wasn't aware of any way of disabling the vacuum system from inside the cockpit I suspected that this was an instructor-induced failure. I told my instructor what I was doing, made the turn on the compass, and expected the instructor to restore the vacuum, but no - this was a genuine failure.
We completed the flight without any further incidents. (The b@stard instructor still put me under the foggles for the diversion and had me do the entire instrument section of the flight partial-panel, too!) During the debrief, instructor told me that he'd noticed the failure a good 5 minutes or so before me. So it seems that it's quite possible to fly an aircraft without looking at the instruments after all
FFF
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Instrumantation
Horses for courses. Yes, indeed.
I tried out an expensive hot-ship microlight recently.
To save weight, instrumentation was a liquid-crystal display, with a row of buttons to bring up whatever particular info you decided you wanted -
Analogue ASI; analogue VSI (both single-pointer or sector-arc display)
Digital Altimeter (buttons to set QFE/QNH); Digital tacho.
Plus a whole lot of other stuff like CHT, EGT, Fuel consumption l/hr, fuel contents (which you had to set zero at the quantity you had in to start with, then read according to what the consupmtion-monitor calculated you'd used since you started). Clock (real-time/elapsed-time). Voltmeter. Flight data recorder. Outside air temp. etc etc.
You get the idea. Clever stuff.
Anyway. trying to pin revs & trim for S&L at the airspeed I wanted, or the ROC/descent, was interesting, to say the least.
The CFI, who was introducing me to this very pretty, sleek, fast aircraft said
"Oh, forget thet lot. Just FLY the thing"
WS
I tried out an expensive hot-ship microlight recently.
To save weight, instrumentation was a liquid-crystal display, with a row of buttons to bring up whatever particular info you decided you wanted -
Analogue ASI; analogue VSI (both single-pointer or sector-arc display)
Digital Altimeter (buttons to set QFE/QNH); Digital tacho.
Plus a whole lot of other stuff like CHT, EGT, Fuel consumption l/hr, fuel contents (which you had to set zero at the quantity you had in to start with, then read according to what the consupmtion-monitor calculated you'd used since you started). Clock (real-time/elapsed-time). Voltmeter. Flight data recorder. Outside air temp. etc etc.
You get the idea. Clever stuff.
Anyway. trying to pin revs & trim for S&L at the airspeed I wanted, or the ROC/descent, was interesting, to say the least.
The CFI, who was introducing me to this very pretty, sleek, fast aircraft said
"Oh, forget thet lot. Just FLY the thing"
WS