Descent rate - Class G
Some years ago a skydiver driver told me he descends at VNE indicated all the way down to circuit height
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For the less initiated amongst us here: why exactly would you need to descend at VNE to CCT height after dropping parajumpers? Why not enjoy a smoother descent?
The faster you get down, the more runs in a day. The more runs in a day, the more money you make. Turbines don't suffer shock cooling and the prop acts like a brake, so why not?
Descent rate depends a lot on the aircraft and its Va. Most light GA aircraft need 700 fpm for a 3 deg approach profile. I use 500 fpm for economy and ATC seem to think I can easily do 2000 fpm. Certainly, its common for ATC to leave me with a TOD that requires 1000 - 1500 fpm or greater to get down to circuit height.
Descent rate depends a lot on the aircraft and its Va. Most light GA aircraft need 700 fpm for a 3 deg approach profile. I use 500 fpm for economy and ATC seem to think I can easily do 2000 fpm. Certainly, its common for ATC to leave me with a TOD that requires 1000 - 1500 fpm or greater to get down to circuit height.
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There is a very interesting thought provoking article called "flight High & fast" which appeared on Vans Aircraft site, well worth a read for anyone operating at high ROD's & high IAS's. Another attached fr some light reading and a wake up call to a LOT of pilots who have no idea about TAS!
I am very mindful of this as I own a high perf SE that can easily bust it's VNE
http://vansaircraft.com/pdf/hp_limts.pdf
http://flyingdonald.********.com/201...t-flutter.html Sorry guys the link doesn't seem to want to paste completely, do a search you'll find it.
I am very mindful of this as I own a high perf SE that can easily bust it's VNE
http://vansaircraft.com/pdf/hp_limts.pdf
http://flyingdonald.********.com/201...t-flutter.html Sorry guys the link doesn't seem to want to paste completely, do a search you'll find it.
Last edited by machtuk; 21st May 2019 at 01:51.
For the less initiated amongst us here: why exactly would you need to descend at VNE to CCT height after dropping parajumpers? Why not enjoy a smoother descent?
I recall a LAME once showing me the result of pilots flying down to the circuit at just below VNE levelling out and putting the first stage of flap out. Serious cracking around the rivets on the flap leading edges. God knows what the stresses were doing to the operating mechanisms.
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Because a lot of skydive operators know Jack Schitt about aircraft and just want the fastest turnaround possible to keep the meatbombs in the air.
I recall a LAME once showing me the result of pilots flying down to the circuit at just below VNE levelling out and putting the first stage of flap out. Serious cracking around the rivets on the flap leading edges. God knows what the stresses were doing to the operating mechanisms.
I recall a LAME once showing me the result of pilots flying down to the circuit at just below VNE levelling out and putting the first stage of flap out. Serious cracking around the rivets on the flap leading edges. God knows what the stresses were doing to the operating mechanisms.
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I recall a LAME once showing me the result of pilots flying down to the circuit at just below VNE levelling out and putting the first stage of flap out. Serious cracking around the rivets on the flap leading edges. God knows what the stresses were doing to the operating mechanisms.
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Replying to Green Goblin's Post
Referencing Green Goblin's post,
In the Navy we called this the "minute to live rule", and it has served as a pretty good guide for me over the years.
In the Navy we called this the "minute to live rule", and it has served as a pretty good guide for me over the years.
Last edited by ClippedWing; 22nd May 2019 at 00:45. Reason: Need to link to a previous post
Hey Machtuck, I note you say the stupidly high rates of descent quoted by Green Goblin were just that - STUPID. But you also said, for comfort, normal ops 500 fpm, anything else is too much. Serious?? Jets coming down from altitude on a normal profile at descent speeds are doing around 2200 =, 2300 fpm. 500??? Dude you need a new pressurisation system.
500fpm is normal in an unpressurised aeroplane.
1000-3000fpm is normal in a pressurised aeroplane.
Anything more than that is a short term intervention for profile management.
Anything less than that is for the same reason.
Don’t hit the ground. Enough said.
1000-3000fpm is normal in a pressurised aeroplane.
Anything more than that is a short term intervention for profile management.
Anything less than that is for the same reason.
Don’t hit the ground. Enough said.
Getting back on thread, it does make it harder to spot dive bombers if they are in the vicinity of the airport. The Mildura near-miss between the Embraer 190 and the GA-8 is a case in point. The GA-8 was 11,000ft at 10.5nm from the runway, diving to 1300ft at 3.5nm. That makes it very hard to pick up. If you're going to dive-bomb near the airport, make sure everybody knows about it.
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Hey Machtuck, I note you say the stupidly high rates of descent quoted by Green Goblin were just that - STUPID. But you also said, for comfort, normal ops 500 fpm, anything else is too much. Serious?? Jets coming down from altitude on a normal profile at descent speeds are doing around 2200 =, 2300 fpm. 500??? Dude you need a new pressurisation system.
i was was ref to unpresurized A/C, seeing as the original thread starter didn't say one way or the other, I thought my comment was obvious!
I fly high perf jets, I think I kinda get it!
Mach. Fair enough, since you're right, no he didn't mention whether pressurised or unpressurised. But neither did you,. Maybe you should have said 500 fpm if unpressurised.
Last edited by Trevor the lover; 25th May 2019 at 11:49.
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"Any aircraft" includes pressurised or unpressurised. The question is not in relation to "best" or "most comfortable" rate of descent - it is about the maximum.
AFAIK there is none - if there was it would put most restriction on pressurised high speed aircraft e.g. RPT jets. It could also pose a problem for vertical aerobatic maneuvers.