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The reason the UK mil use QFE is because they do not like change. It's as simple as that.
Its all been said before but QNH references your altitude with respect to surrounding terrain (not just height above the airfield reference point or runway threshold) and also the base of any controlled airspace above. Both of these things are very useful to know. The only time I used QFE I think was going to Northolt and also when I converted my FAA licence back in the UK and I think it was all part of making the IR test awkward. QFE/ airfield QNH / regional QNH/ standard1013- with all sorts of different transitions to boot, changing the settings every 5 minutes it seemed and that idiotic practice of setting the altimeters to completely different settings at various times in the flight. So, with two altimeters in a spamcan if one is faulty how can you tell a fault even exists? but then of course without a third standby how would you tell which one? The jet aircraft I flew all had 3 pressure alts and nearly all had rad alt so QFE was totally redundant, it told us nothing, in fact using it would limit our "altitude awareness". Don't supa-dupa military aircraft have rad alt's? |
PJ
How's your back? It must be sore with the weight of that sizeable chip on your shoulder!
BV:E |
Originally Posted by PJ
Its all been said before but QNH references your altitude with respect to surrounding terrain (not just height above the airfield reference point or runway threshold) and also the base of any controlled airspace above. Both of these things are very useful to know. The only time I used QFE I think was going to Northolt and also when I converted my FAA licence back in the UK and I think it was all part of making the IR test awkward. QFE/ airfield QNH / regional QNH/ standard1013- with all sorts of different transitions to boot, changing the settings every 5 minutes it seemed and that idiotic practice of setting the altimeters to completely different settings at various times in the flight. So, with two altimeters in a spamcan if one is faulty how can you tell a fault even exists? but then of course without a third standby how would you tell which one? The jet aircraft I flew all had 3 pressure alts and nearly all had rad alt so QFE was totally redundant, it told us nothing, in fact using it would limit our "altitude awareness". Don't supa-dupa military aircraft have rad alt's?
Are you seriously suggesting rad alt is used for anything other than low flying (ie NOT in a radar or visual circuit)? What exactly do you fly? As for the rest....ill-informed and incorrect. Please.....if you don't like it, don't fly it. The rest of us are happy (clearly in our ignorance) and have managed to amass 000's of hours in fast & pointy things (without the assistance of anyone else for many), rotary jobbies and big fat slow things (yes, like the stuff you fly?). QNH may well work for you and that's great but please don't stick your nose in where you clearly don't understand the job we do and the methods we use. Even more bored now and banging out of this thread! :} |
I don't think it's an issue of 'we'll continue to use it because we use it'. I have no problem using QFE, I use it virtually every time I fly. I have no problem driving on the right when I go to Europe or the States; but wouldn't it be better if everyone drove on the correct side of the road? It's probably my OCD that desires uniformity. QFE works just fine but there's no reason to have it. Not that I can see anyway; however as a civ end user I respect the opinions of the more experienced and professional aviators on this sub forum. If you say it's essential then I can't really argue with you.
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Can't believe that this thread has been resurrected - 5 years it's been on here!!!!!
Surely the simple answer to the daft question is "because we want to and we like it!" Fg Off Bloggs Just here to help and take a kicking!:ok: |
because we want to and we like it! |
My My.....imagine that....."Attitude" from a RAF FJ! Whatever is this World coming to these days?:oh:
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If there is only one engine that goes quiet soonish after take off and no Martin Baker letdown option things are likely to be a bit busy. Doing mental arithmetics to add elevation to the QNH is one more thing likely to get in the way of speedy decision making when every second counts.
Why are you turning back Bloggs? Cos I've got enough height. But you've got altitude set. §h!t :uhoh: |
Gee.....does that mean all these years and Zillions of flight hours....the Yanks have done it all wrong? You have any accident statistics that would prove your point?
Are US Accident rates higher than the UK for such a reason? Surely you know of what you speak so you should be able to corroborate that or you would not be saying what you are. I have not flown out of my home airport in probably thirty years but I still remember the Field Elevation is 960 feet. How hard is the Math(s) to keep track of your cardinal heights which in our case were 400 feet and 800 feet. Even if I merely rounded up to 1000 Feet and then added my numbers, would it really make a damn? Considering acceptable Altimeter Instrument error is 70 feet plus or minus, and some variation in actual Barometric Pressure due to normal pressure changes between recordings, just how accurate does one need to be in the math(s)? What tolerance do you demand in determining a height at which you will turn back or not? One foot....Ten Feet....a Hundred Feet....Five Hundred Feet? Is it the Altimeter Indication that is your final factor or your Mark I Eyeball and Brain working in conjunction with each other that is the final bit of information that facilitates that decision? |
My My.....imagine that....."Attitude" from Louisiana! Whatever is this World coming to these days?
I've used both (a lot) am happy with either and really don't care. If the military want to use QFE then let them. fwiw in the training environment with lots of visual ccts I found QFE easier both as student and instructor. |
I'll not bore you with the details, but last week I was flying between the downwind leg and the runway, but in the "wrong" direction, at 800 feet (QFE) while a Typhoon who was downwind was heading towards me at 1,200 feet (QFE) just a little to my right.
It's quite common for us to be in mixed height circuits, and going in different directions. It all works rather well on QFE. I suppose we could just learn to fly at 839 feet or 1,239 feet (or 539 feet for Helicopters) but I don't want to be looking for a 39 foot mark on the altimeter. As for landing, I don't normally look at the altimeter after 300 feet in the descent, by then I'm looking out the front. |
Can you fly to a one foot accuracy no matter which "mark" you are looking for?
The key is for everyone to be using the same Altimeter setting whichever is chosen as the Reference and stick to the correct Height or Altitude. Years ago we had three BarAlts on our helicopters and no RadAlt.....and in Norwegian waters the Field SOP in the Ekofisk was based upon RadAlt Height which the Helicopter Service aircraft had in addition to their BarAlts. They did not provide QFE settings as they used QNH for their BarAlts. Thus a small problem in traffic separation standards. |
Boudreaux
There's a phrase that a friend of mine taught me once that I think applies here:
It's not wrong, it's just different. It appears that you're the only one who has really got that upset about it so maybe it's time to just sleeping dogs lie? We do things differently sometimes and it works for us (as I've previously said I couldn't really care either way). At some point in history you guys started driving on the wrong side of the road and changing the way you spell things but we long since stopped caring about it. BV |
BV,
You are absolutely correct! I am quite upset and just cannot leave Sleeping Dogs alone! The key is for everyone to be using the same Altimeter setting whichever is chosen as the Reference and stick to the correct Height or Altitude. Perhaps you are looking for insult where none is offered. |
Are US Accident rates higher than the UK for such a reason? On Wednesday the 21st, the Air Force Accident Investigation Board held a news conference at the home of the Thunderbirds - Nellis Air Force Base - to announce what caused an F16 to crash last September. According to the accident investigation board report the pilot, 31-year-old Captain Chris Stricklin, misinterpreted the altitude required to complete the "Split S" maneuver. He made his calculation based on an incorrect mean-sea-level altitude of the airfield. The pilot incorrectly climbed to 1,670 feet above ground level instead of 2,500 feet before initiating the pull down to the Split S manoeuvre. |
You refer to the Mountain Home Crash I assume.
The difference in altitudes at Nellis and Mountain Home may have contributed to the pilot's error. The airfield at Nellis is at 2,000 feet whereas the one at Mountain Home is at 3,000 feet. It appears that the pilot reverted back to his Nellis habit pattern for s aplit second. Thunderbird commander Lt. Col. Richard McSpadden said Stricklin had performed the stunt around 200 times, at different altitudes during his year as a Thunderbird pilot. McSpadden says Stricklin is an exceptional officer. "He is an extremely talented pilot. He came in here and made an honest mistake," says Lt. Col. McSpadden. But that mistake has cost Stricklin his prestigious spot on the Thunderbird team. "He's assigned to Washington D.C.," says McSpadden. "He's working in the Pentagon there in one of the agencies." The maneuver the pilot was trying to complete is called the "Split S Maneuver." The stunt requires that the pilot climb to 2,500 feet. Investigators say Stricklin only climbed to 1,670 feet before he went into the spinning roll. The board determined other factors substantially contributed to creating the opportunity for the error including the requirement to convert sea level altitude information from the F-16 instruments - to their altitude above ground and call out that information to a safety operator below. But the Air Force has now changed that as a result of the crash. Thunderbird pilots will now call out the MSL (mean-sea-level) altitudes as opposed to the AGL (above-ground-level) altitudes. Thunderbird pilots will now also climb an extra 1000 feet before performing the Split S Maneuver to prevent another mistake like the one on Sep.14, 2003 from happening again. Captain Chris Stricklin has been in the Air Force since 1994 and flew with the Thunderbirds for the first season now. He has logged a total of 1,500+ flight hours and has received numerous awards. He served as a flight examiner, flight instructor and flight commander. |
You refer to the Mountain Home Crash I assume Use QFE, just look for the correct number on the dial; same number every time. Use QNH then you have to do a sum - albeit fairly simple - then look for this number on the dial. Different number at each venue. Get the sum wrong and... Well it made a great photo! |
Must be a FJ thing....otherwise they would be NAV's if they could do math(s).:uhoh:
Mountain Home AFB has an elevation of 3146 feet. Would an RAF aircraft be able to use a QFE setting at that elevation? |
And all because they cannot add, it would appear When Stricklin realized something was wrong, he exerted maximum back stick pressure and rolled slightly left to ensure the aircraft would impact away from the crowd should he have to eject, the Air Force said. He ejected when the aircraft was 140 feet above the ground. There was no other damage to military or civilian property. Also, the board determined other factors substantially contributed to creating the opportunity for the error to occur, including the requirement for demonstration pilots to convert AGL elevations to MSL altitudes, and performing a manoeuvre with a limited margin of error. Instead of just zeroing the altimeter to deck level as a result of the crash, procedures have been changed to require that Thunderbird pilots climb an extra 1,000 feet before starting the Split-S manoeuvre. |
Same ole Pprune...
We're on a new page now so rather than reading back through previous pages we'll just have the same conversation over and over ad nauseam.
BB you know the answer to your question so why ask? If I were to fly an RAF aircraft to Mountain home (or somewhere of similarly lofty elevation) I would use QNH. Does that make me better than you because I am eminently capable of operating safely on either system? BV:rolleyes: |
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