how safe are these aircrafts
Paxing All Over The World
Antoninus One of the problems faced by operators of turbo-props in hot and high conditions is not knowing how many pax are going to show up. The flight may not be fully booked but some folks do a 'walk up' booking and have only briefcases. This might mean that the a/c departs full but no overloaded for the conditions. But if those last couple of pax had big cases - it might put them over limits. The carrier will have historic data telling them how many times in a month of the hot season this is a problem. They will try to balance the times they have to offload pax or bags as a commercial decision.
My nephew was a Captain on the Jetstream 41 in South Africa for several years and had these problems almost every day. That a/c is a low winged 20 seater turbo prop and until the pax showed up - you had no idea how much of a problem you would have. On some sectors at some stages of the year, the booking system was set to not allow a full number of passengers, as they would hit the weight limits and it was better to run the flight with reduced capacity than not at all. This still gave problems if the system had not been set correctly and all the seats HAD been sold!! Or, on days when the temperature was much higher than expected and so they reached temperature limitations sooner in the year. To combat this, some of the a/c had a special booster system for take-off, that used additional special fuel (Water/Meth mix) to increase the SHP (Shaft Horse Power) for departure. In the longer term, this causes extra wear and tear on the engine but is fully certified and monitored of course.
Lastly, although they carried very little freight an extra box or two could cause a problem. Not least as some of the ground staff did not fully understand the principle that an a/c is limited by WEIGHT rather than by VOLUME. In other words, if the loader could see that there was still spare volume in the baggage comparment - then they would keep stuffing boxes and cases into it until it was full.
So when knowing that they would be weight limited, on the walkaround, one duty was to check how much 'extra' had been loaded without the pilot knowing!
The ATR is larger than the J41 but is subject to the same problems. As, indeed, is the mighty 747. For there is always a limit to the weight that may be lifted. At Heathrow (my local field) the problem is slight as the field is only about 100' amsl and usually cool. Although the day I flew Concorde, we had a problem as the temp hit 100F (37.7C).
But a simple example: leaving from LHR for Johannesburg, a 744 will (typically) be rolling for 45/50 seconds before rotation. On the return flight, when departing JNB, they will be rolling for 60/65 seconds and the runway has to be much longer to compensate for the air being both thinner and warmer. Also, JNB is at 5,500' (approx) and temps up to 35C in the middle of the day. So the long hauls leave early in the morning or in the early evening. The jet engine produces thrust by the differential temperature between the air going into the front and what it has reached by the brief second that it emerges from the tail pipe. The turbo-prop is subject to the same factors. (I sit to be corrected on any technical detail as I am Pax not crew!)
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"I tell you, we are here on Earth to fart around, and don't let anybody tell you any different." Kurt Vonnegut, Jr.
My nephew was a Captain on the Jetstream 41 in South Africa for several years and had these problems almost every day. That a/c is a low winged 20 seater turbo prop and until the pax showed up - you had no idea how much of a problem you would have. On some sectors at some stages of the year, the booking system was set to not allow a full number of passengers, as they would hit the weight limits and it was better to run the flight with reduced capacity than not at all. This still gave problems if the system had not been set correctly and all the seats HAD been sold!! Or, on days when the temperature was much higher than expected and so they reached temperature limitations sooner in the year. To combat this, some of the a/c had a special booster system for take-off, that used additional special fuel (Water/Meth mix) to increase the SHP (Shaft Horse Power) for departure. In the longer term, this causes extra wear and tear on the engine but is fully certified and monitored of course.
Lastly, although they carried very little freight an extra box or two could cause a problem. Not least as some of the ground staff did not fully understand the principle that an a/c is limited by WEIGHT rather than by VOLUME. In other words, if the loader could see that there was still spare volume in the baggage comparment - then they would keep stuffing boxes and cases into it until it was full.
So when knowing that they would be weight limited, on the walkaround, one duty was to check how much 'extra' had been loaded without the pilot knowing!The ATR is larger than the J41 but is subject to the same problems. As, indeed, is the mighty 747. For there is always a limit to the weight that may be lifted. At Heathrow (my local field) the problem is slight as the field is only about 100' amsl and usually cool. Although the day I flew Concorde, we had a problem as the temp hit 100F (37.7C).
But a simple example: leaving from LHR for Johannesburg, a 744 will (typically) be rolling for 45/50 seconds before rotation. On the return flight, when departing JNB, they will be rolling for 60/65 seconds and the runway has to be much longer to compensate for the air being both thinner and warmer. Also, JNB is at 5,500' (approx) and temps up to 35C in the middle of the day. So the long hauls leave early in the morning or in the early evening. The jet engine produces thrust by the differential temperature between the air going into the front and what it has reached by the brief second that it emerges from the tail pipe. The turbo-prop is subject to the same factors. (I sit to be corrected on any technical detail as I am Pax not crew!)
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"I tell you, we are here on Earth to fart around, and don't let anybody tell you any different." Kurt Vonnegut, Jr.
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"Lastly, although they carried very little freight an extra box or two could cause a problem. Not least as some of the ground staff did not fully understand the principle that an a/c is limited by WEIGHT rather than by VOLUME."
hi PAXboy,
I think none of the ground staffs here at our airports fully understand the principle you mentioned above.
I could, though never tried, pay the ground staffs an extra money as little as USD 10 for a normally USD 50 worth of excess luggage.
NOw I remember, there is a very old manual-scale used to weigh the baggage at c/in counter, and my golf bag weighs differently every time I check in.
Thanks for sharing the info, I had never thought of it. I will bring up this issue to the airlines manager, hopefully they understand this simple principle.
hi PAXboy,
I think none of the ground staffs here at our airports fully understand the principle you mentioned above.
I could, though never tried, pay the ground staffs an extra money as little as USD 10 for a normally USD 50 worth of excess luggage.
NOw I remember, there is a very old manual-scale used to weigh the baggage at c/in counter, and my golf bag weighs differently every time I check in.
Thanks for sharing the info, I had never thought of it. I will bring up this issue to the airlines manager, hopefully they understand this simple principle.
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Statistics
Boeing publishes WW stats on western jet aircraft at http://www.boeing.com/news/techissues/pdf/statsum.pdf
The F28, 707 and DC8 come out as the least safe aircraft still in service.
You can go into aircraft types individually on aviation safety network. The turboprop stats are at http://aviation-safety.net/database/....php?type=prop
To make fair comparisons, you need to compare aircraft by numbers of take/offs and landings, or something similar, which I am not doing below.
It does not say how many of each type are in service. There have been 6 ATR42 accidents with fatalaties. One was a suicide with just one pilot on board. One was an overrun on landing, with just one fatality.
There have been five ATR72 accidents with fatalaties.
The Dehavilland Dash 7 and 8 have had four each. The Fokker 50 has had 3, and the F27 has had 17.
The Boeing 737/200 has had 49 accidents with fatalities.
Momo
The F28, 707 and DC8 come out as the least safe aircraft still in service.
You can go into aircraft types individually on aviation safety network. The turboprop stats are at http://aviation-safety.net/database/....php?type=prop
To make fair comparisons, you need to compare aircraft by numbers of take/offs and landings, or something similar, which I am not doing below.
It does not say how many of each type are in service. There have been 6 ATR42 accidents with fatalaties. One was a suicide with just one pilot on board. One was an overrun on landing, with just one fatality.
There have been five ATR72 accidents with fatalaties.
The Dehavilland Dash 7 and 8 have had four each. The Fokker 50 has had 3, and the F27 has had 17.
The Boeing 737/200 has had 49 accidents with fatalities.
Momo
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Momo, number of accidents w/ fatalities isn't very meaningful uintil one realizes how many planes of that type are in service. IIRC at least ten times as many 737/200s were built than Dash 7s. One hardly ever sees a Dash 7 these days but there are still a number of old 737/200s in mainline USA service. Didn't Southwest just retire their last one?
Denver can be hot and high, but very seldom humid. It was said that United, which has a very big presence at DEN, was unhappy that the earliest 737s couldn't do DEN to Chicago on a hot day with a full load. That was from the old DEN airport. The new airport has much longer runways than the old one had when the first 737s came out.
Denver can be hot and high, but very seldom humid. It was said that United, which has a very big presence at DEN, was unhappy that the earliest 737s couldn't do DEN to Chicago on a hot day with a full load. That was from the old DEN airport. The new airport has much longer runways than the old one had when the first 737s came out.
Last edited by seacue; 29th Aug 2005 at 03:22.
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Yup -
re: previous
Yes, as I point out, the comparison is not fair.
On the hot and high discussion: South African, for example, does New York to Joburg non-stop, but has to stop to refuel going the other way, because they cannot take off with a full load of fuel. Of course the fuel weighs much more than the passengers plus baggage, which would not be the case on ATR routes shorter than about 1300 km.
Momo
Yes, as I point out, the comparison is not fair.
On the hot and high discussion: South African, for example, does New York to Joburg non-stop, but has to stop to refuel going the other way, because they cannot take off with a full load of fuel. Of course the fuel weighs much more than the passengers plus baggage, which would not be the case on ATR routes shorter than about 1300 km.
Momo
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Just to follow on from earlier points. I as a punter really enjoy flying with props. For instance, i have flown on the rather spiffing Dash Q400 from flybe, and they are great. Some older or smaller turboprops are not so good, as usually the airlines try to queeze in too many passengers.
I just wonder about budget airlines though - wouldn't it make financial sense for some routes to use aurcraft like Q400's for example Glasgow or Edinburgh to belfast - for which EZY uses a 737 - for a tiny flight. Are the turboprops (modern ones) not much more thrifty on really short hops?
Anyway - the Q400's they use at flybe are great, and the legroom is not too bad (but not brilliant - better than EZY).
I just wonder about budget airlines though - wouldn't it make financial sense for some routes to use aurcraft like Q400's for example Glasgow or Edinburgh to belfast - for which EZY uses a 737 - for a tiny flight. Are the turboprops (modern ones) not much more thrifty on really short hops?
Anyway - the Q400's they use at flybe are great, and the legroom is not too bad (but not brilliant - better than EZY).
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Load factor
I think load factor is the most important. Fuel per passenger mile is considerably less on a full modern 737 or A319 than on a full Q400. So, if you are able to get the large aircraft reasonably full, the economics work. If you can only get a Q400-size passenger list for the flight, it is of course more economical to fly that.
Momo
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"One would hear constant engine noise through out the flight, but sometimes the noise level is reduced or completely gone for few seconds and I get really nervous when that happens. "
What you are probably experiencing is the pilot altering the angle of the propellors during the flight. This causes a noise or frequency change. On the ATR 72 200 and in fact on the ATR 300 it is common to bring the propellors from 86% NP in the climb to 77% NP for the cruise. It is also an ATR requirement to alter the angle of the propellors when entering icing conditions. So in effect you may have a few changes depending on actual conditions experienced on the route. Having the propellors at 77% reduces the noise and enhances pax comfort.
As for the safety, I've been flying both these aircraft for a time now and have had no worrying incidents with the aircraft yet. They are as safe or as dangerous as the next aircraft in my opinion!!
What you are probably experiencing is the pilot altering the angle of the propellors during the flight. This causes a noise or frequency change. On the ATR 72 200 and in fact on the ATR 300 it is common to bring the propellors from 86% NP in the climb to 77% NP for the cruise. It is also an ATR requirement to alter the angle of the propellors when entering icing conditions. So in effect you may have a few changes depending on actual conditions experienced on the route. Having the propellors at 77% reduces the noise and enhances pax comfort.
As for the safety, I've been flying both these aircraft for a time now and have had no worrying incidents with the aircraft yet. They are as safe or as dangerous as the next aircraft in my opinion!!
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Interesting to note from the Boeing research the next most 'dangerous' aircraft after the 707, DC8 and F28 is........
The MD11.
Bit worrying when you think the above aircraft have almost exclusively ended up in third world operator's hands whereas the MD11 is still in use by airlines like KLM and a host of US cargo carriers and is still up there.
Never did like the old deathstar...
The MD11.
Bit worrying when you think the above aircraft have almost exclusively ended up in third world operator's hands whereas the MD11 is still in use by airlines like KLM and a host of US cargo carriers and is still up there.
Never did like the old deathstar...
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Of course, there is one very big danger of looking at statistics:
The statistics do not look at the reasons for fatalities! The entire Douglas DC10 fleet worldwide was grounded following the American Airlines crash at Chicago (ORD) costing the aviation industry billions. The world's press unfairly labelled it a "death ship" and this undoubtedly led to the Douglas Airplane Company going bust and being absorbed into Boeing's giant maw!
In reality, American Airlines had taken shortcuts, in the name of manpower/cost savings, with the procedures for engine replacement - yet Douglas never managed to sell another DC10!!!
The ATR is a perfectly safe, aircraft. Uncomfortable, yes (but then, a "T" type tail will always cause more motion at the rear of the aircraft than a normal tail plan) but certainly not unsafe!
The statistics do not look at the reasons for fatalities! The entire Douglas DC10 fleet worldwide was grounded following the American Airlines crash at Chicago (ORD) costing the aviation industry billions. The world's press unfairly labelled it a "death ship" and this undoubtedly led to the Douglas Airplane Company going bust and being absorbed into Boeing's giant maw!
In reality, American Airlines had taken shortcuts, in the name of manpower/cost savings, with the procedures for engine replacement - yet Douglas never managed to sell another DC10!!!
The ATR is a perfectly safe, aircraft. Uncomfortable, yes (but then, a "T" type tail will always cause more motion at the rear of the aircraft than a normal tail plan) but certainly not unsafe!
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Well...
Well, the DC-10 accident was quickly followed by the Turkish Airlines one over Paris where a poorly designed freight door opened in flight.
Momo
For the Denver-Colorado Springs hop, I remember one of the accidents was in 1991. A work colleague died in it.
Given that a friend also died in the SR111 disaster, I certainly abandoned all "It could never happen to me" thinking.
Momo
Momo
For the Denver-Colorado Springs hop, I remember one of the accidents was in 1991. A work colleague died in it.
Given that a friend also died in the SR111 disaster, I certainly abandoned all "It could never happen to me" thinking.
Momo
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I think the MD-11 killed (McDonnell) Douglas, you'll find, when fuel burn was significantly beyond what was promised.
The merger with Boeing, among other things, removed the last American widebody alternative and thus drove Congress into the arms to Boeing in the post 9/11 KC767 scandal when the Defence Science Office had recommended expanding the KC-10 fleet - funny that.
As for the safety or otherwise of the ATR fleets - the ATR order book has been turning over very quickly compared to our local Q400 competitor and has outlasted the S2000 so the market thinks they're worth it.
The merger with Boeing, among other things, removed the last American widebody alternative and thus drove Congress into the arms to Boeing in the post 9/11 KC767 scandal when the Defence Science Office had recommended expanding the KC-10 fleet - funny that.
As for the safety or otherwise of the ATR fleets - the ATR order book has been turning over very quickly compared to our local Q400 competitor and has outlasted the S2000 so the market thinks they're worth it.
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I flew in an ATR again this morning, and all seemed to be OK.
and while cruising, I saw another ATR flying probably on same altitude but in good distant, I suppose. From that distant, it sized as small as a pencil.
However, is ATR equipped with that traffic/anti-collision device ?
and while cruising, I saw another ATR flying probably on same altitude but in good distant, I suppose. From that distant, it sized as small as a pencil.
However, is ATR equipped with that traffic/anti-collision device ?
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You want to be daring? Fly Binter Canarias from one airport to another in the Canary Islands.. 
I didn't know what i was gettiny myself into when i boarded their ATR-72... and i'll safely say now, i'll never fly on one again! i respect they are safe, but i like to feel safe
http://www.airliners.net/open.file/668348/L/
http://www.airliners.net/open.file/665692/L
I didn't know what i was gettiny myself into when i boarded their ATR-72... and i'll safely say now, i'll never fly on one again! i respect they are safe, but i like to feel safe
http://www.airliners.net/open.file/668348/L/
http://www.airliners.net/open.file/665692/L
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I agree with SamGuest. They may be safe but I like to feel safe. I've been a regular with BMI on LBA-GLA, but on the occasions an ATR was substituted for the usual EMB, the PAX were not happy!
When it was a regular occurrence a year or so back, I switched to EMA until the 145s returned- a longer drive, but somehow I felt safer on the M1 in rush hour than in the ATR!
Apart from some "exciting" landings at LBA in high wind, the 145's convey a lot more comfort and confidence then the ATR (see associated thread re the Jungle Jet, seem like both the PAX and Pilots like them.
Antoninus quote;
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"Ah.. The Jumbo.. Big plane, so big that you almost forget you're in a plane.. So big that when you fly through those big mid-atlantic turbulences halfway between the US and Europe, you barely feel the bumps."
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Worst turbulence I have ever felt was on a VS 747 off the eastern coast of the US - incredible.
When it was a regular occurrence a year or so back, I switched to EMA until the 145s returned- a longer drive, but somehow I felt safer on the M1 in rush hour than in the ATR!
Apart from some "exciting" landings at LBA in high wind, the 145's convey a lot more comfort and confidence then the ATR (see associated thread re the Jungle Jet, seem like both the PAX and Pilots like them.
Antoninus quote;
============
"Ah.. The Jumbo.. Big plane, so big that you almost forget you're in a plane.. So big that when you fly through those big mid-atlantic turbulences halfway between the US and Europe, you barely feel the bumps."
============
Worst turbulence I have ever felt was on a VS 747 off the eastern coast of the US - incredible.
Last edited by Victor Meldrew; 8th Sep 2005 at 12:27.
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Unfortunately, do to the nature of modern society (ie. lack of education - especially in the sciences, modern management practices and the manner and method of media reporting) and man's basic make-up - passengers become the group of people least able to determine safety or otherwise of an aircraft.
The facts of life in the First World are this: No government, operator or crew will knowingly allow any aircraft to depart if they feel that it's safety is un-reasonably compromised. This does not mean that there is no risk, just an acceptable one. Yes, the quality of ride on a turboprop aircraft is not generally as high as a jet - but it's level of safety (or exposure to risk) is no different.
Living is not risk-free. There are only two certainties: Death and Taxes.
The facts of life in the First World are this: No government, operator or crew will knowingly allow any aircraft to depart if they feel that it's safety is un-reasonably compromised. This does not mean that there is no risk, just an acceptable one. Yes, the quality of ride on a turboprop aircraft is not generally as high as a jet - but it's level of safety (or exposure to risk) is no different.
Living is not risk-free. There are only two certainties: Death and Taxes.
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Flown it (as in drove it not rode it):
ATR42-500 and ATR72-500: Lovely to fly hand flew most of the time (was for a magazine article) really very forgiving and a lot of fun to fly. The -500s have had a bit stiffening work done to the upper fuselage and have six blade props all of which makes for a reduction in vibration and noise. Only downsides - I'd like to see some nose wheel authority via the pedals (just the tiller on the ATRs) and you want to be careful you fly the nose wheel on on landing.
Dash 8-Q400: Again lot's of fun to fly bags of grunt and it goes like the provibial waste product off a exacvation implement. Had a few probs with realiability early on but I gather that's been pretty sorted now.
I've been told (by them that know) that the seat mile costs on the the 70 seaters (Q400/ATR72) are pretty much the same as the 737-3,4,7,800 so for routes where you can't fill a larger a/c they're just the job.
While fuel pricing stays where it is (Jet fuel is about 400% it's May 2001 price) the superior fuel economy of the turboprops will continue to make them attractive to airlines (no matter what the punters think!). The proff of the pudding...both ATR and Bombardier are shifting them at rates much much higher (almost twice) their most optmistic forecasts of just a few years ago.
Interestingly although the Saab 2000 is out of production they are rarer than hen's teeth on the second hand market (even with SWISS phasing out their fleet (they were the largest operator). Meanwhile, in the US there are more S340s (out of production for even longer) in airline service now than there were a year ago.
ATR42-500 and ATR72-500: Lovely to fly hand flew most of the time (was for a magazine article) really very forgiving and a lot of fun to fly. The -500s have had a bit stiffening work done to the upper fuselage and have six blade props all of which makes for a reduction in vibration and noise. Only downsides - I'd like to see some nose wheel authority via the pedals (just the tiller on the ATRs) and you want to be careful you fly the nose wheel on on landing.
Dash 8-Q400: Again lot's of fun to fly bags of grunt and it goes like the provibial waste product off a exacvation implement. Had a few probs with realiability early on but I gather that's been pretty sorted now.
I've been told (by them that know) that the seat mile costs on the the 70 seaters (Q400/ATR72) are pretty much the same as the 737-3,4,7,800 so for routes where you can't fill a larger a/c they're just the job.
While fuel pricing stays where it is (Jet fuel is about 400% it's May 2001 price) the superior fuel economy of the turboprops will continue to make them attractive to airlines (no matter what the punters think!). The proff of the pudding...both ATR and Bombardier are shifting them at rates much much higher (almost twice) their most optmistic forecasts of just a few years ago.
Interestingly although the Saab 2000 is out of production they are rarer than hen's teeth on the second hand market (even with SWISS phasing out their fleet (they were the largest operator). Meanwhile, in the US there are more S340s (out of production for even longer) in airline service now than there were a year ago.