experienced first mechanical failure today on 5th lesson
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experienced first mechanical failure today on 5th lesson
Nothing to write home about but...
Thought probability would dictate that my first failure of any kind would take more than 5 flights to happen.
During my run-up I found that the suction gauge was reading zero regardless of the engine RPM. Asked the instructor if we should go back to parking but he said it wasn't a big deal for a VRF flight, and apparently, on the ground, it appeared that the attitude indicator and DG were working. Turns out they worked for the entire flight, elthough I have no idea what the vacuum level was..if it was "in the green" or on the verge of not being enough.
On the way home I decided that had it been a night flight or a foggle flight, I would not have flown the condition.
It's probably just instrumentation (the suction gauge). Will ask next week after its fixed. Interestingly this 172 had its vacuum pump replaced yesterday. I thing the shop forgot about the whole "make sure it actually works" part.
Did I do right by allowing the flight to get off the ground? The instructor is the instructor but my butt is mine.
Thought probability would dictate that my first failure of any kind would take more than 5 flights to happen.
During my run-up I found that the suction gauge was reading zero regardless of the engine RPM. Asked the instructor if we should go back to parking but he said it wasn't a big deal for a VRF flight, and apparently, on the ground, it appeared that the attitude indicator and DG were working. Turns out they worked for the entire flight, elthough I have no idea what the vacuum level was..if it was "in the green" or on the verge of not being enough.
On the way home I decided that had it been a night flight or a foggle flight, I would not have flown the condition.
It's probably just instrumentation (the suction gauge). Will ask next week after its fixed. Interestingly this 172 had its vacuum pump replaced yesterday. I thing the shop forgot about the whole "make sure it actually works" part.
Did I do right by allowing the flight to get off the ground? The instructor is the instructor but my butt is mine.
For a day VFR flight, the suction gauge is not needed. However given that the vacuum pump was replaced, it looks like the hose leading to the suction gauge was left flopping in the engine compartment instead of connected to the new pump, but it's unlikely it would come to grief.
How well the vacuum pump tolerates unfiltered air is another question, but likely the cap for the suction gauge fitting was left on.
I would have shut down, opened the cowl and had a good look for anything else left dangling. After replacement of a component, a test flight or runup to verify proper operation and installation should be done. You and the instructor did the test flight
How well the vacuum pump tolerates unfiltered air is another question, but likely the cap for the suction gauge fitting was left on.
I would have shut down, opened the cowl and had a good look for anything else left dangling. After replacement of a component, a test flight or runup to verify proper operation and installation should be done. You and the instructor did the test flight
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Instrument failure is insidious. The instruments may appear to work, but the assumption must always be made where the vacuum gauge is low or zero, that the instrument indications which use a vacuum source are not reliable.
The same may be true for high vacuum indications; this is usually the result of a blocked instrument air filter, and also suggests low gyro RPM, and an unreliable instrument indication.
Flying airplanes is all about dealing with abnormal and emergency situations; it's why we train, and it's wh we have procedures.
Vacuum pumps fail with some regularity; I've seen a lot of them fail shortly after installation. While wet pumps seldom fail, dry carbon-vane vacuum pumps often fail.
A good habit to get into with respect to maintenance issues is to ask to be shown what went wrong, each time you experience a problem. Any school worth their weight in wet salt will take the time to show you, and it's an excellent learning experience for you.
No pilot should be without an aircraft flight manual for the aircraft that he or she is flying. I've always strongly advocated that one obtain and read the aircraft maintenance manual, because it's got a lot more, and a lot better information than the pilot handbook.
The same may be true for high vacuum indications; this is usually the result of a blocked instrument air filter, and also suggests low gyro RPM, and an unreliable instrument indication.
Flying airplanes is all about dealing with abnormal and emergency situations; it's why we train, and it's wh we have procedures.
Vacuum pumps fail with some regularity; I've seen a lot of them fail shortly after installation. While wet pumps seldom fail, dry carbon-vane vacuum pumps often fail.
A good habit to get into with respect to maintenance issues is to ask to be shown what went wrong, each time you experience a problem. Any school worth their weight in wet salt will take the time to show you, and it's an excellent learning experience for you.
No pilot should be without an aircraft flight manual for the aircraft that he or she is flying. I've always strongly advocated that one obtain and read the aircraft maintenance manual, because it's got a lot more, and a lot better information than the pilot handbook.
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Dry Vac pumps have a 600 hour life, most people who are opperating VFR seem to forget this and run the pump untill it fails.
The faiure of new Vac pumps is usualy due to FOD getting in to the system during fitting of the new pump.
The faiure of new Vac pumps is usualy due to FOD getting in to the system during fitting of the new pump.
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Interestingly this 172 had its vacuum pump replaced yesterday.
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Welcome to your first lesion on maintenance. Get a book, make a note and go back over them in 10 years. Chances are it will make interesting reading. You did the right thing flying provided the weather was good. There are 1000’s of machines flying with none of the vacuum instruments you had even installed. The important thing is that you assume they have all failed and preferably cover them up.
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I'll throw out a different point of view :
FAR 91.7 states :
My interpretation is that you should have returned to the ramp and had the aircraft looked at.
The aircraft would not necessarily be in an unsafe condition for flight but if equipment is inoperative then it is meant to be placarded as such and remarks entered in the aircraft logbooks.
It is irrelevant that many aircraft do not have suction systems etc - the law calls for appropriate action if it is fitted - and you would definitely have failed a practical test had you done that on the test.
This an all too common attitude amongst pilots - who to quote the FAA
If you see more of this attitude I would start to question the professionalism of the staff / school.
FAR 91.7 states :
§ 91.7 Civil aircraft airworthiness.
(a) No person may operate a civil aircraft unless it is in an airworthy condition.
(b) The pilot in command of a civil aircraft is responsible for determining whether that aircraft is in condition for safe flight. The pilot in command shall discontinue the flight when unairworthy mechanical, electrical, or structural conditions occur.
(a) No person may operate a civil aircraft unless it is in an airworthy condition.
(b) The pilot in command of a civil aircraft is responsible for determining whether that aircraft is in condition for safe flight. The pilot in command shall discontinue the flight when unairworthy mechanical, electrical, or structural conditions occur.
The aircraft would not necessarily be in an unsafe condition for flight but if equipment is inoperative then it is meant to be placarded as such and remarks entered in the aircraft logbooks.
It is irrelevant that many aircraft do not have suction systems etc - the law calls for appropriate action if it is fitted - and you would definitely have failed a practical test had you done that on the test.
This an all too common attitude amongst pilots - who to quote the FAA
seem to have a too higher threshold to what should stop a flight
Avoid imitations
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The flight was VFR and the pump was working.
The instructor decided the aircraft was airworthy, albeit not fully serviceable, so the flight could safely go ahead.
What would have been the consequences of subsequently failed suction instruments on a purely VFR flight? Not a lot.
I think the man who signed the tech log used his noddle and made the correct decision.
The instructor decided the aircraft was airworthy, albeit not fully serviceable, so the flight could safely go ahead.
What would have been the consequences of subsequently failed suction instruments on a purely VFR flight? Not a lot.
I think the man who signed the tech log used his noddle and made the correct decision.
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I agree the vac system is probably not legally needed for day VFR, but
I sadly have to disagree with.
Most instructors haven't got a clue about airworthiness, and many schools collude with dodgy maintenance companies to minise costs. It is an endemic practice.
I started my PPL with a school which operated absolute crap planes despite having an AOC for charter work. During the preflight (on this particular type one opens up a part of the cowling) I found some bare wires which could touch something, cause a spark, and ignite any fuel leak. The instructor said it was OK. Some weeks later, with evidently nobody else noticing this, the said cable had come right out of of the connector. I refused to fly the plane. The instructor got a bit peeved off and said "it only goes to the landing light; just don't switch on the landing light". I took a walk to another school and chucked away 10-20hrs of training, plus some exam passes which got "lost". The school later featured in a celebrated accident in which the judge commented that if he could shut them down he would. No way would the CAA act, because they were paying them nice AOC fees.
The instructor is still there, still thumbing through the airline job adverts, a decade later. He is probably the CFI (gosh) now
So I would not take any instructor's word for the airworthiness of an aircraft. If it looks dodgy to somebody intelligent, it probably is.
And with no gyro instruments, if you enter IMC, you will plummet pretty fast. It's not smart.
The instructor decided the aircraft was airworthy, albeit not fully serviceable, so the flight could safely go ahead.
Most instructors haven't got a clue about airworthiness, and many schools collude with dodgy maintenance companies to minise costs. It is an endemic practice.
I started my PPL with a school which operated absolute crap planes despite having an AOC for charter work. During the preflight (on this particular type one opens up a part of the cowling) I found some bare wires which could touch something, cause a spark, and ignite any fuel leak. The instructor said it was OK. Some weeks later, with evidently nobody else noticing this, the said cable had come right out of of the connector. I refused to fly the plane. The instructor got a bit peeved off and said "it only goes to the landing light; just don't switch on the landing light". I took a walk to another school and chucked away 10-20hrs of training, plus some exam passes which got "lost". The school later featured in a celebrated accident in which the judge commented that if he could shut them down he would. No way would the CAA act, because they were paying them nice AOC fees.
The instructor is still there, still thumbing through the airline job adverts, a decade later. He is probably the CFI (gosh) now
So I would not take any instructor's word for the airworthiness of an aircraft. If it looks dodgy to somebody intelligent, it probably is.
And with no gyro instruments, if you enter IMC, you will plummet pretty fast. It's not smart.
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So I would not take any instructor's word for the airworthiness of an aircraft. If it looks dodgy to somebody intelligent, it probably is.
They have an aircraft which they have "made" unairworthy.
They get regular instructors/pilots and regular citizens to check the aircraft out.
The pilots do the worst. Regular citizens perform above a "trained" pilot. Go visit them at Sun and Fun!
so the flight could safely go ahead.
So I would not take any instructor's word for the airworthiness of an aircraft. If it looks dodgy to somebody intelligent, it probably is.
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Oh I would never have simply brushed off a zero-vacuum reading on a checkride. Nor would I had I been doing a solo or a post-PPL flight. What happened is the instructor being in the plane made me feel safer. However, he shouldn't have. This was a mistake on my part. I learned a big lesson here: when my life is on the line, the decision is mine. I don't care if Chuck Yeager is in the right seat, if I say the aircraft is in a no-fly condition then, for my lesson at least, it's in a no-fly condition.
After the flight, I found out that this particular aircraft was, in a pinch, serviced by the field's only maintenance shop, and that the owner of the flight school hates this shop and 99.9% of the time uses a shop that's "a couple of airfield's" west that, according to my buddy that works for the flight school, has an outstanding service record and does impeccable work. The owner was pissed to see our squawk...NOT happy at all with the local shop.
What I didn't mention in my OP is that I decided that I did not like this particular instructor. He's not my regular CFI but rather someone I got when I scheduled a flight at the last minute to make up for one last weekend that got nuked by a low ceiling. I like to get in at least 2 a week. The reason I did not like him is because on take-off, we nearly departed the south side of runway 27. It was my first flight in a 172 (normally I use a 152) and I was not ready for the need for more right rudder during T/O roll. In a few short seconds, I was all the way at the extreme left edge of the runway. I believe my wheels actually left the ground at the very last milliseconds worth of asphalt...had I delayed rotation and longer we would have been in the grass. This could have been a real mess.
I kicked myself really hard last night for not getting on that rudder with more authority. However, I am not paying the guy in the right seat to just sit there and go for a ride. I didn't know my mere 5th lesson was going to essentially be a solo flight. While I'm sure I'll get some replies blaming me entirely for nearly wiping out on takeoff, I really think maybe the CFI should have gotten on that rudder to help me out. Has we crashed, I would hate to think I would be 100% liable for the cost of repairs or a new aircraft. I thought the CFI was the PIC but apparently not. Trial by fire I guess...
Well today I was back to my regular instructor. We did rectangular course, some navigation work, and I spent an hour wearing the foggles. Wind and turbulence were *intense* and incessant but I figure that makes for better training. So far most of my flights have been very bumpy as I train during the season change. I hope that when it comes time for me to do a solo, or rather a flight where the CFI stays on the ground in the case of yesterday's lesson, that the dang winds in this area finally calm down.
After the flight, I found out that this particular aircraft was, in a pinch, serviced by the field's only maintenance shop, and that the owner of the flight school hates this shop and 99.9% of the time uses a shop that's "a couple of airfield's" west that, according to my buddy that works for the flight school, has an outstanding service record and does impeccable work. The owner was pissed to see our squawk...NOT happy at all with the local shop.
What I didn't mention in my OP is that I decided that I did not like this particular instructor. He's not my regular CFI but rather someone I got when I scheduled a flight at the last minute to make up for one last weekend that got nuked by a low ceiling. I like to get in at least 2 a week. The reason I did not like him is because on take-off, we nearly departed the south side of runway 27. It was my first flight in a 172 (normally I use a 152) and I was not ready for the need for more right rudder during T/O roll. In a few short seconds, I was all the way at the extreme left edge of the runway. I believe my wheels actually left the ground at the very last milliseconds worth of asphalt...had I delayed rotation and longer we would have been in the grass. This could have been a real mess.
I kicked myself really hard last night for not getting on that rudder with more authority. However, I am not paying the guy in the right seat to just sit there and go for a ride. I didn't know my mere 5th lesson was going to essentially be a solo flight. While I'm sure I'll get some replies blaming me entirely for nearly wiping out on takeoff, I really think maybe the CFI should have gotten on that rudder to help me out. Has we crashed, I would hate to think I would be 100% liable for the cost of repairs or a new aircraft. I thought the CFI was the PIC but apparently not. Trial by fire I guess...
Well today I was back to my regular instructor. We did rectangular course, some navigation work, and I spent an hour wearing the foggles. Wind and turbulence were *intense* and incessant but I figure that makes for better training. So far most of my flights have been very bumpy as I train during the season change. I hope that when it comes time for me to do a solo, or rather a flight where the CFI stays on the ground in the case of yesterday's lesson, that the dang winds in this area finally calm down.
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What happened is the instructor being in the plane made me feel safer. However, he shouldn't have. This was a mistake on my part. I learned a big lesson here: when my life is on the line, the decision is mine
and that the owner of the flight school hates this shop and 99.9% of the time uses a shop that's "a couple of airfield's" west
As regards turbulence, it is often bad on hot summer days, unless you get above the white fluffy clouds. At this time of the year it is usually cured by flying higher. You are probably flying close to some terrain. Instrument flight is very hard in turbulence; you can't read the compass so are relying on the DI which may not be accurate, but fortunately one rarely flies on instruments at low levels when enroute. In the departure/approach phases, yes.
Avoid imitations
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And with no gyro instruments, if you enter IMC, you will plummet pretty fast. It's not smart.
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IF you enter IMC? Gosh. So how do aircraft like gliders fly without them?
If it's no big deal for a glider to enter IMC with no attitude indication, please tell me how they do that sir because it blows my mind...
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Limited panel instrument time is taught for a reason, if you do have vac failure in IMC you have your VSI, ASI, altimeter and turn coordinator to reference. With these you dont really need an artificial horizon, its just a luxury
For the original poster: You're in the USA I gather so the aircraft was unairworthy. That's not to say that it's not possible to fly with a failed suction guage, but there are certain procedures that must be followed I.A.W. the FARs.
* IF it's operated with an MEL, then the procedure in the MEL for that failure must be followed.
* IF it doesn't have an MEL then you need to comply with FAR 91, part of which deals with failed equipment. The precis is that the failed item must be removed (mechanic's job) OR disabled & placarded unserviceable. Either way it must be noted in the aircraft's maintenance logbook.
* IF it's operated with an MEL, then the procedure in the MEL for that failure must be followed.
* IF it doesn't have an MEL then you need to comply with FAR 91, part of which deals with failed equipment. The precis is that the failed item must be removed (mechanic's job) OR disabled & placarded unserviceable. Either way it must be noted in the aircraft's maintenance logbook.
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I remember that on one of my first cross country flights I also noticed the failure of the vacuum pump, meaning no gyros whatsoever. On the taxi way I told my instructor that we have 0 reading from the vacuum indicator .. he looked over my shoulder and said "yes, you're right. Well, if they could find Germany 70 years ago, at night, with only a compass and a map, I'm pretty sure we'll be able to find LRxx. At least you'll know how to do things if vacuum pump fails you in air during a cross country flight" So we went on and I was amazed how much I've learned about VFR navigation in that particular flight. I wouldn't worry so much for a local VFR flight without gyros. I even know some Diamonds Katana that are not even fitted with such.
So we went on and I was amazed how much I've learned about VFR navigation in that particular flight. I wouldn't worry so much for a local VFR flight without gyros. I even know some Diamonds Katana that are not even fitted with such.