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Hyperthetical for all you IFR people.

flying dog

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Ok folks. Here is a doozy.


Hyperthetical plane, so please don't pick me on the exact specs.


IFR flight. Nominal engines. You pick.


NIGHT. Clouds - with storms developing outside your intended track.


It is a long trip with multiple segments. There is NO GPS! So there is no "cheating" in this scenario.


You are doing it the old way.


Until now everything has been good. Times, fuel, etc etc.




You encouter turbulance and the plane is rocked for many long minutes. The rocking makes it extremely difficult to keep your altitude and heading; and the autopilot has dis-engaged. YOU are flying.


You are at enough of a safe altitude at this time to know you are not going to have any CFIT. However there are mountains about 53 minutes either side of your track.


After the turbulance, you notice you are off course by about 30 degrees. To re-itterate: It has been MANY minutes. Not just a few. About 50 minutes have passed since you last checked the time. Your airspeed is 240 Kts.


As you scan the panel, the DI is still spinning and you have a vacuume problem. Fumbling around for the torch, and you can't find it. Therefore you can not see the compass.


There are NO LANDING PLACES marked on your charts within any reasonable distance.


This together with the fact you don't know where you are..... Well: Enough said.


The HSI is still working as is the VSI and altimetre and luckily the Airspeed indicator.


You have nominal fuel for the flight logged and the engine/s are ok. You slow down to 170 Kts indicated, that is about 20 kts above stall speed. It starts to rain and it is getting cold outside. Vis is virtually non-existant.


This is full instrument flying.


Checking you ADF / VOR and DME they are all out of range and so can't tell you where you are.


Panic starts to set in as you realise the situation.


Reaching for the radio you transmit on the last known frequency and get NO REPLY.


Tuning to 121.5 you also get no reply.




What would YOU do?



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Well it is just a scenario with which I am "playing".


I know there are many rules about how things progress and things which happen which preclude others happening.


I am wording it in aviation terms because this is an aviation based group.


I could have made it marine based, but I don't know how many people here have boats.


It is simply a question with given paramaters and I am interested what people would do.



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What you said:


Well, the dash 8 flying near Italy with the wrong ammount of fuel is similar. The pilots wasted time wondering why the engine wasn't working and didn't concentrate of feathering the props and heading for land.


The plane which I mistakenly identified with the blown gear down light is another one.


Then there is the plane flying in PNG - I think - and the ATC vectored them slightly wrong and the pilots were confused also, they crashed. Similar.


The jet which was going through some ice/hail storm and the ATC wanted them higher than they were. When the crew put on the power the engines failed because of the build up of hail inbetween the compressors stages and the engines catastrofically failed. The plane crashed all killed.


It is only a question and excusing HOW you get there, the question is WHAT WOULD YOU DO.....


It is only hyperthetical.



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Dog, I wouldn't be there, simple as that.


IFR isn't VFR in clouds, it is a whole different set of rules and for numerous reasons the scenario you have come up with is not feasible. It has nothing to do with feathering props or catastrophic engine failures.


Do you want me to go into all the various reasons?



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Guest Sharp End
However there are mountains about 53 minutes either side of your track.After the turbulance, you notice you are off course by about 30 degrees. To re-itterate: It has been MANY minutes. Not just a few. About 50 minutes have passed since you last checked the time.


What would YOU do?

Umm, F-D, there's no way on earth any IFR pilot would have flown for 50 minutes without the vaguest notion of time or position. This scenario is, if I'm best guessing, three minutes to a CFIT yes? WAY before the 50 minute point (i.e as soon as things started going pear shaped) I personally would have RTB'd.



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Faults with the questions.


IFR flight rules mean that you track either from aid to aid i.e. ndb to vor or ndb etc. OR you use RNAV (gps) so you are always heading to somewhere and always know where you are.


Secound. Unless you are private ifr you will have standby instruments so if your vac pump fails you will have back up electric instruments. If your van pump fails and then you have your elec system fail (really really bad day) your battery will be able to maintain the instruments for a suitable time to get you somewhere to land.


Thirdly if the HSI is working you will know your heading so you would work out an intercept to get yourself back on track.


Fourthly if you are in rain and ice in an aircraft that isn't approved for flight into you shouldn't be there!


So either the person who is flying the plane shouldn't be flying the aircraft or you are really making yourself work hard on flight sim!!


All the other situations would have been avioded if the crew had of acted appropriatly ie one flies the plane the other person sorts out the problem. It works for single pilot ops aswell - always make sure someone is flying the plane!!!!





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... or you are really making yourself work hard on flight sim!!

I was going to suggest hit Alt F4 and play solitare instead. 066_naughty.gif.fdb194956812c007d0f5d54e3c692757.gif


But things are just so touchy :dousing: around here these days. :ne_nau:049_sad.gif.af5e5c0993af131d9c5bfe880fbbc2a0.gif


After thought:


Try it again rephrased as a boat question Dawgie. The concept got bogged down by the reasons why it shouldn't happen in aviation....



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Seems I really hit a nerve asking the question. As said before: It is HYPERTHEICAL.


Ok, it breaks every rule in the book. I also said that it is a translation of another situation worded as best I can to suit flying.


Mazda, sure I don't mind you explaining the "rules" which were broken, but please don't tear strips off me for asking. Again: It is hyperthetical.


Sharp end, yeah, ok. 3 minutes and CFIT. I added the 50 minutes only for the sake of it and to give a bit better operating margin.


Oh what is RTB? Return to Base? (Just guessing.)



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Guest Sharp End

Hi F-D,


Yep... RTB = return to base... Follow the emergency checklist, sort out the problem and if it remains RTB, OR if really serious, land at the nearest suitable. That's what I'd be doing as soon as I encountered the first problem.





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Dog, you haven't actually given me much to go on - i.e. pvt/charter/airwork? What class of airspace? In or out of radar coverage?


Here are a vew points though. There are very strict tracking tolerances that must be adhered to. Such as 1/2 scale deflection on the VOR and +/-5 degrees on the ADF. If you go beyond this, you MUST notify ATC immediately. So there is no way you would suddenly realise you are out of navaid range, and there's no way you would suddenly notice you are 30 degrees off track.


If in radar coverage, it's quite likely that ATC will be on to you anyway.


You must understand that you don't just fly along for 50 minutes waiting for the turbulence to stop. You would be flying the aircraft, scanning and tracking the whole time. You would know the time, you must advise ATC if your estimate at the next position is out by more than 2 minutes so you are always aware of the time and thinking about the time at your next estimate.


GPS isn't "cheating" is could be approved for sole or primary navigation, but not having one is OK. No autopilot? Who cares! Vacuum failure? From scanning you would know something wasn't right, so you'd go onto standby instruments or partial panel. If having trouble tracking partial panel, see the paragraph above about advising ATC.


Can't contact ATC due to no VHF coverage? IFR MUST be capable of constant contact with ATC. If in areas with marginal or no VHF coverage, the aircraft must have HF radio, so if you lost VHF you would talk to ATC on HF.


Can't find your torch? Unlikely. Most people have it on a lanyard around their necks (and turned on) for take off, so i can't see how it would have suddenly disappeared, and most people carry a spare which they keep handy.


Just a few points Dog, I really don't want to go into this in too much detail because the scenario is not realistic.



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No worries.


I knew when I wrote it that there were problems with how I worded it. However, please bare in mind it is HYPERTHETICAL and though how I got there was not really realistic, I was more interested in WHAT someone would do *IF* they were presented with that scenario.


That's all. I now know that how I discribed it had problems in how I "put you there" but.....


Anyway.... Doesn't matter.



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I'll have a go...I'd turn around and head back. Hopefully the back door is still open and there may be more options back where I came from. Pushing on into a bad position would only make things worse.


If that didn't work, I'd do these ones...086_gaah.gif.afc514336d60d84c9b8d73d18c3ca02d.gif



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im pretty sure the compass would still be working.... if you know your off track by 30 deg, you can use the 1/60 rule, and get back on track, you know the time and airspeed, so you should have a rough estimate of the location. you still have the 3 keys to navigate, heading speed and timer. with these you should be able to get close enough to a navaid to get a fix, or back in radio range.



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Guest ozzie

The closest i've ever heard for this situation was in the US during the seventies in a Baron at night. The pilot fell asleep. Woke up in cloud over the Rockies long way past his let down point, one engine had failed, shortly followed by the other. Managed to put it down on a highway.



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The pilot WHAT 088_censored.gif.2b71e8da9d295ba8f94b998d0f2420b4.gif (fell asleep???)You've got to be kidding!



Sounds pretty detrimental... though people do fall asleep at the wheel quite often.


And a Baron up high with Autopilot, is probably a reasonably comfortable way to sleep... :confused:



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I just watched the 60 minutes report on the norfolk island ditch. Seems clear from the report that the pilot made quite a few bad decisions in the planning and the actual flight. The only thing he did manage to get right was the ditch itself. They did mention however that acording to PEL-AIR, the flight had no need for the usual safety precautions like an alternate. Can you believe that? Can anyone here confirm that? What about 45min reserve? Anyhow, surely this flight was under IFR. Or should have become so. It seems the rules don't always make rotten conditions impossible to encounter.



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Yes, but be carefull trusting tottaly in what 60 minutes have to say. The flight was IFR, they made 3 attempts at an NDB appch, but at minima were still in soup.


We shouldn't be to harsh without knowing the facts,


I have read the report. It is a little damming, but the captains actions after the ditching were more of a concern.


Anyway, its off topic.. sorry



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Guest basscheffers

In the preliminary report, ATSB confirmed they did not require fuel for an alternate as the forecast gave no clue that Hamilton might be below minimums.


The aircraft can easily take enough fuel to make an alternate, and you should be better safe than sorry. So probably a case of knowingly putting people at risk (while being legal!) to save a bit of money. Fuel is probably more expensive in Samoa and so is flying with more weight.



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Ant there is no regulation at the moment to carry 45 minutes fixed reserve, it is a recommendation. However if your operations manual stipulates 45 minutes (or anything else) that is what you must carry. Plus a percentage variable reserve for commercial ops, usually 10%. The recommended fixed reserve for jets is 30 minutes.


Planning an alternate is another story.


Have a look at the ATSB report!



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Guest check-in

Flying Dog you mentioned that you could have made it marine-based. Then you would know that the safest place to go in a storm is out to sea unless you can make safe haven. i.e. as far from reefs, lee shores and shoals as possible. The aeronautical equivalent of being safely at sea is to be as high as possible. In your scenario, with functioning engines and basic instruments, firewall the throttles, climb at max angle to 10,000 feet which we know clears all terrain in Australia. If your scenario is on the west coast of the USA or in PNG, 18,000 ft does it, and anyone flying in those areas would likely have oxygen. For good measure, reverse course (you said the HSI was OK) on the basis that you did not hit anything getting into this pickle, so you shouldn't hit anything extracting yourself.


If not already religious, consider a quick conversion to whatever faith tickles your fancy.



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Thanks that is a good reply.


(Sorry there was another one but I have just been reading the other posts.)


Ok, something which I see is "confusing":


I said the HSI and so you all say I should know my heading.


I said/used HSI as that is what I believe people call what I called the AH.


If I am wrong, I am sorry. It was badly explained to and/or interpreted by me.


I meant that the instrument required to maintail "straight and level" was working. As the given pilot couldn't see the horizon, the AH would be used.


On that ditching......


Ok, there were problems with the events leading up to the "accident", however, I am curious if they should be split into two different things:


1 - the flight planning




2 - the running out of fuel and ditching




I appreciate there are rules the pilot SHOULD obide when flying, but if he is a commercial pilot on a well done route, the "boffins" would know the rules as much as the pilot should.


Given the forecast said the weather was ok at the destination, I guess there are problems.




Well, if the plane carries 'X' fuel and can make it from A to B, but C - an alternative - is outside the range...... I guess that would make it the wrong plane for the trip?


If there are planning problems who's "fault" is it? The pilot's or the company's?



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