11900 ft

[frankmcm]

Any experience of high altitudes?

 

I stupidly flew under cloud trying to get home a week ago. The base closed down and suddenly I had no horizon visible. I elected to "climb through" as I had a bank indicator. Didnt get there until over 10000ft.

 

I am appropriately chastened by the experience and wont go there again, but I am interested if this is a common experience.? Jab 450UL with 2200 engine.

 

 

[Guest davidh10]

Frank;

 

As I'm a relatively new pilot. my only experience with having to take avoiding action due to cloud was on a flight where the morning had been foggy and I took off after it lifted to just above circuit height, on the basis that it was going to burn off during the flight.

 

About 16 miles out, the cloud base had forced me down to 500' AGL and visibility was at minima for VFR. While there was a way, by flying through what was effectively a tunnel toward a higher cloud base, my decision at the time was to abort the flight and return to the point of departure.

 

The cloud did lift later in the day, so I could have completed the flight ok by pressing on, however the decision had to be taken at the time and conditions could have gone either way. The thought reinforcing my decision was the possibility of losing the back-door.

 

Given that recreational pilots in Australia are not permitted to fly in IMC (or over 5,000' except for terrain clearance), I doubt anyone would admit to it in a public forum, even if they had done so. Apart from the rules, the education that without appropriate training and instruments, such a venture is virtually certain to end in death should prevent anyone from attempting such a venture. Elsewhere in these forums, an instructor has indicated that his experience of even GA pilots (non-IFR rated) who have therefore had some instrument training, is that many lose control of the aircraft very quickly in IMC.

 

 

[facthunter]

high altitude flight. (above 10,000')

 

Are you concerned about the altitude OR the cloud or the illegality?

 

Regarding the altitude, you are required to have oxygen available to go over TEN thousand, although TWELVE thousand is quoted in some circles.

 

Depending on your fitness and age, you will possibly experience some loss of facilities even below these altitudes. You can get this information from sources on human factors.

 

As far as the aeroplane is concerned it will get less responsive due to the reduced air density. The other factor is that the indicated airspeed is a lot less than what your real airspeed is and you could exceed speeds at which flutter could occurr on descent IF you were not aware of this.

 

you are not supposed to be ABOVE 5,000 unless there is a compelling reason, with RAAus rules. Nev

 

 

[Guest Andys@coffs]

A quick google maps of "Airstrip" will quickly show that RAA isnt an issue.

 

On the otherhand CFICARE's suggestions of airframe icing might be more an issue than the northern parts of our landmass

 

To my thinking if the altitude is such that you talk about it in terms of flightlevels rather than feet and the engine (assuming not turbo'd or jet) is only capable of producing a fraction of its ground rated hp and the altitude you attained was what it was because you simply couldnt climb anyfurther then in general you dont want to be there.

 

Of course the follow on question is what did you do next, assuming the cloud cover was extensive?

 

Andy

 

 

[Warmbrak]

Thanks for sharing your story Frank - I read an accident report just 2 weeks ago of a gent who was trying to get home in his Cessna 206 Stationair with full G1000 cockpit that flew into cloud and decided to press ahead instead of turning around. Fortunately he flew alone and was the only casualty in that case.

 

I would not think that this is a common occurrence, and I would recommend the same cautious approach that David took. Unless one has a suitable rating and aircraft to fly in those conditions, best would be to do a 180 standard turn and rtb.

 

 

[dazza 38]

Im glad your still with us Frank, to tell your story.Are you still living in Ireland ?

 

 

[dazza 38]

Are you concerned about the altitude OR the cloud or the illegality?Regarding the altitude, you are required to have oxygen available to go over TEN thousand, although TWELVE thousand is quoted in some circles.

Depending on your fitness and age, you will possibly experience some loss of facilities even below these altitudes. You can get this information from sources on human factors.

 

As far as the aeroplane is concerned it will get less responsive due to the reduced air density. The other factor is that the indicated airspeed is a lot less than what your real airspeed is and you could exceed speeds at which flutter could occurr on descent IF you were not aware of this.

 

you are not supposed to be ABOVE 5,000 unless there is a compelling reason, with RAAus rules. Nev

A example of a aircraft reducing VNE as altitiude increases-

Pipistrel Sinus

 

Sea Level- 122 kts

 

3300 ft -116 kts

 

10 000 ft- 105 kts

 

 

[Tomo]

Jabiru aircraft are rated to a ceiling of 10,000ft. So I don't think the airframe vs height would be the huge factor here.

 

The conditions, and that experience - I'm glad you're with us today mate.

 

 

[XP503]

frankmcm, you're right about one thing....

 

It was a stupid thing to do and you should be more careful in future or stay on the ground.

 

 

[frankmcm]

Sounds like it's not common then, which is reassuring.

 

I arrived at altitude because, once committed to climbing, I had little good alternative. Not IMC rated, but able to hold the wings level and correct airspeed etc because I had once practised with a colleague.

 

I had got into trouble in the first place by flying under and dodging rain to get home. This was the really big learning experience for me, and I will in future be the first to turn around. I had not appreciated just how quickly a cloud base can jump down on you. Once the perspective of the horizon had been lost I didnt have a safe way to turn round. Maybe descending would have given me back some visibility, but I had to make a judgement call, so I went up. I had anticipated that I would find clear air much lower, and was getting more worried all the way up beyond 5000.

 

Scottish ATC were great, allocating me a dedicated controller until I got down. I fortunately did find a hole and descended through it. Eventually made it to a retired military airfield. I learned more on that trip than I have ever done, and I appreciate my good fortune in being able to talk about it.

 

Legality probably not an issue as I was doing my best to get out of trouble. Judgement certainly an acknowledged problem as it got me into the trouble in the first place. Flying is a complex business, and some messages dont get properly assimilated until suddenly they become very relevant. This was my learning opportunity and I got away with it.

 

 

[XP503]

Glad you got away with it and have learned, and hopefully others will read and learn how quickly you can get into trouble. Many others, including experienced instrument rated pilots were not so lucky, they are now dead.

 

 

[Barefootpilot]

Frankmcm.

 

I have no idea about the height a Jab can go too but your story is a good one. Lets just hope a few people read it and learn a little from it and it saves them from experiancing it themselves! It sounds like you have learnt your lesson.

 

 

[Guest Mad Dave]

Hypoxia

 

As mentioned in the earlier threads one risk is Hypoxia.

 

One thing that never fails to interest me is taking passnegers who smoke to 8500 or 9500, and stop talking to them for a while, it is amazing how many fall asleep!

 

 

[frankmcm]

I note and appreciate all the comments. Learning would seem to be the key message, and accepting a bit of flak helps hammer home the learning points. In my day job we make a big deal about "significant event analysis", and I see this thread as some sort of a gesture in that direction.

 

I have'nt see too many similar posts on the forum. The big incidents with twisted metal get aired and discussed, and we all have an opportunity to absorb the messages. However I suspect that there might be incidents which are resolved before any damage is done, yet which could usefully be aired.

 

I will let you know when next I get a feeling that something is not quite right in the Jab.....

 

 

[eightyknots]

Words that come to mind are..Hypoxia

 

Airframe icing

 

Disorientation

 

Possible violation of controlled airspace

 

Possible collision with IFR traffic

 

Fail to maintain VMC....

 

I could go on...

Carby icing

 

 

[Barefootpilot]

You shouldn't get too much carby ice with the throttle wide open climbing through it.

 

 

[Bruce Tuncks]

Altitude flying

 

Here's some history of altitude limitations..

 

During WW2, ferry flights of troops over the Atlantic used 14000 ft (no pressure cabins or oxygen) for 6 hours. Some troops suffered, so they lowered the limit to 12000 ft and I think this is still the case in the USA.

 

To show we can go even better than the US, here in Australia we got a legal limit of 10,000 ft. There are towns and cities in the world above this height.

 

Without oxygen, 99% of healthy non-smokers would be ok to at least 16,000 ft, probably with some reduction in mental acuity. Lots of glider pilots have exceeded this lots of times.

 

This is still only a bit more than halfway up Mount Everest, which is 29000 ft. But people are very variable, so the rule to keep everybody completely safe, including smokers, is the 10,000 ft one.

 

This is not to be taken as encouragement to go so high. The dispensation which allows us to go over 5000 ft when safety demands it was a hard-won right, and we shouldn't risk losing it.

 

Cloud flying is a different issue, I concur with what has been said here.

 

.......Bruce

 

 

[biggles5128]

Those of us in this forum who have instrument ratings will reinforce the need to practice under the hood or in IMC and shoot regular approaches to stay safe. The idea that the few hours a GA pilot gets on the clocks while obtaining his/her licence will save your bacon is sometimes a hard learnt lesson. Even a few months away from IMC will see an experienced instrument pilot get the leans, the only thing that helps you then is discipline, which is only gained by correct teaching and regular exposure to actual IMC.

 

:)

 

 

[jabpilot]

Rod Stiff advised of a MOSAD officer whilst in Bundy took a standard Jab to almost 25,000 ft. The aircraft are certainly capable. There have also been (a small few) climbers of Mount Everest who have succeeded without oxygen. All this doesn't mean this will work for us and we will survive. We almost certainly won't. But don't throw your hands in the air and panic if you make a bad decision and find yourself higher than you should be. Maintain composure and aviate first to get out of that situation as soon as practicable.

 

 

[rage83]

high altitude flight. (above 10,000')Are you concerned about the altitude OR the cloud or the illegality?

 

Regarding the altitude, you are required to have oxygen available to go over TEN thousand, although TWELVE thousand is quoted in some circles.

 

Depending on your fitness and age, you will possibly experience some loss of facilities even below these altitudes. You can get this information from sources on human factors.

 

As far as the aeroplane is concerned it will get less responsive due to the reduced air density. The other factor is that the indicated airspeed is a lot less than what your real airspeed is and you could exceed speeds at which flutter could occurr on descent IF you were not aware of this.

 

you are not supposed to be ABOVE 5,000 unless there is a compelling reason, with RAAus rules. Nev

Just a thought, Are we not allowed up to 10000ft yes essentially VFR I guess thats 9500ft??? Was I missinformed about this change in the rules, If so I appoligise.

 

The point I am making here is yes he still went above a legal limit but only by 1900ft or so. It does sound alot worse when someone is percieved to be nearly 6000ft above a legal limit.

 

Other comments stand true tho.

 

Cheers,

 

Rob

 

 

[Guernsey]

Just a thought, Are we not allowed up to 10000ft yes essentially VFR I guess thats 9500ft??? Was I missinformed about this change in the rules, If so I appoligise.The point I am making here is yes he still went above a legal limit but only by 1900ft or so. It does sound alot worse when someone is percieved to be nearly 6000ft above a legal limit.

 

Other comments stand true tho.

 

Cheers,

 

Rob

I thought the same ie 9,500 ft. I think it was in one of the recent Mags. I'll have to check it out.

Alan.

 

 

[rage83]

http://www.comlaw.gov.au/Details/F2011L00617

 

Yeah we can 10000ft is quoted. Aircraft is radio equiped.

 

 

[Guest ozzie]

Although it states 10,000ft there is no cruising in the transition layer of 10,000-11,000ft so that should bring one back to the lower odds of 9500ft.

 

 

[pudestcon]

10000' is acceptable and is not part of the transition layer....10001' is though...

I thought hemispherical levels were a requirement above 5000', am I wrong?

Pud

 

 

[Guest Crezzi]

I thought the same ie 9,500 ft. I think it was in one of the recent Mags. I'll have to check it out.Alan.

Quite correct Alan. Appropriate cruising levels are not just for planning they are mandatory above 5000' (CAR173). If you can't maintain VMC at 9500' you have to descend.

 

However, since the OP mentioned talking to Scottish ATC, he either has a phenomenal radio setup or he's not obliged to follow CASA's rules.

 

Cheers

 

John