B777Neuss From Germany, joined Aug 2007, 152 posts, RR: 0 Posted (5 years 8 months 1 week 5 days 2 hours ago) and read 3179 times:
So my next question,
on some aircraft I have seen red squares on top of the fuselage with the words "cut here in emergency". Is there something special under the skin, e.g. are there less stringers (what I don´t believe) or no air conditioning tubes? And whose decision is it to mark these areas?, not every airline has this squares.
KELPkid From United States of America, joined Nov 2005, 5932 posts, RR: 4 Reply 1, posted (5 years 8 months 1 week 5 days 1 hour ago) and read 3158 times:
It's a marking for ARFF (Airport Rescue & Fire Fighting) crews to know where to cut in case it is necessary to rescue individuals trapped inside the airframe. And yes, indeed, there are usually less stringers in the areas marked
Celebrating the birth of KELPkidJR on August 5, 2009 :-)
EMBQA From United States of America, joined Oct 2003, 9286 posts, RR: 13 Reply 2, posted (5 years 8 months 1 week 5 days 1 hour ago) and read 3154 times:
You answered your own question. It's just the easiest area to cut in case of an emergency. As for why...? I only see it on some airlines from Europe and not in the US. Maybe something to do with regulations.
"It's not the size of the dog in the fight, but the size of the fight in the dog"
Rwessel From United States of America, joined Jan 2007, 1989 posts, RR: 2 Reply 3, posted (5 years 8 months 1 week 4 days 17 hours ago) and read 3026 times:
On some aircraft the "cut here" lines avoid potentially dangerous items inside the aircraft. For example, aircraft with ejection seats will typically have a number of pyrotechnic devices scattered around the cockpit to do things like sever lines, blow/shatter the canopy, etc. (in addition to the seat rocket, of course). Also, things like high pressure oxygen lines are best avoided, and some aircraft have fuel lines and other nasties in that general vicinity.
Viscount724 From Switzerland, joined Oct 2006, 21488 posts, RR: 24 Reply 4, posted (5 years 8 months 1 week 4 days 16 hours ago) and read 3004 times:
But why do those "cut here in emergency" markings exist only on aircraft of certain airlines, even when operating the identical type? Many carriers do not have such markings on their aircraft. US or Canadian carriers don't have them to the best of my recollection and the same is true for many European carriers
I am guessing that it may be a regulatory requirement of certain governments only.
Viscount724 From Switzerland, joined Oct 2006, 21488 posts, RR: 24 Reply 7, posted (5 years 8 months 1 week 3 days 23 hours ago) and read 2820 times:
Quoting HAWK21M (Reply 5): Quoting Viscount724 (Reply 4):
Many carriers do not have such markings on their aircraft
Any Examples.
Try and find an A.net photo of a US or Canadian-registered aircraft with the "cut here in emergency" markings. And I am almost certain that KL/LH/LX aircraft do not have them, which seems to be confirmed by a quick photo search. I think that carriers with those markings are in the minority.
I have a feeling that the requirement may date back to some historic British requirement and was adopted mainly by certain carriers that had close links to the UK or copied their regulations. Kuwait Airways, for example, has those markings on their aircraft and Kuwait was a British protectorate until 1961.
OPNLguy From , joined Dec 1969, posts, RR: Reply 8, posted (5 years 8 months 1 week 3 days 19 hours ago) and read 2737 times:
Quoting Rwessel (Reply 3): Also, things like high pressure oxygen lines are best avoided,
Most aircraft built since the early 1980s don't have plumbed oxygen systems like the earlier aircraft did--the newer ones use chemical oxygen generators in the PSUs overhead of the seats.
Quoting Rwessel (Reply 3): and some aircraft have fuel lines and other nasties in that general vicinity.
I can't think of single aircraft that had fuel lines running above a passenger compartment. Check that, the Shorts 330/360 turboprops have a damn tank up there. (Never did make much sense to me--putting fuel above passengers where it could potentially leak on passengers below...)
Don't know what to attribute the different marking rules to.. I've see diagrams for the ARFF folks that tell them where the critical stuff, so they know where to look/cut, even if the markings aren't there...
2H4 From United States of America, joined Oct 2004, 8950 posts, RR: 62 Reply 9, posted (5 years 8 months 1 week 3 days 19 hours ago) and read 2735 times:
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Quoting OPNLguy (Reply 8): Never did make much sense to me--putting fuel above passengers where it could potentially leak on passengers below...
I've often wondered about Cessna's logic in placing ashtrays mere inches from fuel lines in the 172/182/etc...
HAWK21M From India, joined Jan 2001, 31201 posts, RR: 58 Reply 10, posted (5 years 8 months 1 week 3 days 15 hours ago) and read 2693 times:
Quoting Viscount724 (Reply 7): Try and find an A.net photo of a US or Canadian-registered aircraft with the "cut here in emergency" markings. And I am almost certain that KL/LH/LX aircraft do not have them, which seems to be confirmed by a quick photo search
KELPkid From United States of America, joined Nov 2005, 5932 posts, RR: 4 Reply 11, posted (5 years 8 months 1 week 3 days 15 hours ago) and read 2683 times:
Quoting 2H4 (Reply 9): I've often wondered about Cessna's logic in placing ashtrays mere inches from fuel lines in the 172/182/etc...
2H4
What kind of idiot smokes in a Cessna, anyways? Good way to run up your avionics and vacuum powered gyro repair bill, not to mention destroy the interior
Celebrating the birth of KELPkidJR on August 5, 2009 :-)
KELPkid From United States of America, joined Nov 2005, 5932 posts, RR: 4 Reply 12, posted (5 years 8 months 1 week 3 days 5 hours ago) and read 2616 times:
Quoting OPNLguy (Reply 8): I can't think of single aircraft that had fuel lines running above a passenger compartment. Check that, the Shorts 330/360 turboprops have a damn tank up there. (Never did make much sense to me--putting fuel above passengers where it could potentially leak on passengers below...)
I would imagine that all high wing types are in the same boat-Dash 8's, ATR's, Doriner 327/328, BAE 146, etc.
Celebrating the birth of KELPkidJR on August 5, 2009 :-)
2H4 From United States of America, joined Oct 2004, 8950 posts, RR: 62 Reply 13, posted (5 years 8 months 1 week 2 days 19 hours ago) and read 2510 times:
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Quoting KELPkid (Reply 11): What kind of idiot smokes in a Cessna, anyways?
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