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Descent rate - Class G

Old 19th May 2019, 23:36
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Descent rate - Class G

After an incident in class G airspace recently, I ponder the question.... with no radar guidance/advice, what do you feel should logically be the greatest rate of descent (or climb for that matter) for any aircraft?

If there is a reg, whoops, I havenít checked :-)

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Old 19th May 2019, 23:50
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I'm not aware of the incident but the last thing we need is a rate of decent limit. Completley impractical for skydiving ops, and pretty impractical for all the high capacity jets and turbo props (especially the ones operating above 10000ft), and no doubt impractical for some others.

Airmanship suggests easing the ROD/ROC near crossing traffic you are aware of, but this is class G we are talking about.

The question should rather be focused on how appropriate class G is in a given area.
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Old 20th May 2019, 00:43
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What descent rate do skydiving aircraft get up to? Iím guessing turboprops would be much higher.
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Old 20th May 2019, 01:12
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pretty quick descent....

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Old 20th May 2019, 01:20
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Squawk, you'll need to give us some info on the incident before we comment.

IMO, as high as possible to minimise time in Ledspace!!
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Old 20th May 2019, 02:10
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Let me just say that the attached video above sums up the issue very nicely!

Perhaps not quite as quick in this case, but 100% relevant.
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Old 20th May 2019, 02:29
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Originally Posted by Squawk7700 View Post
What descent rate do skydiving aircraft get up to? Iím guessing turboprops would be much higher.
3500fpm is normal in a C208 and up to 7000fpm in a Blackhawk conversion C208 or PAC750/Cresco
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Old 20th May 2019, 03:28
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Under normal Ops 500' ROD for comfort, anything higher is unusual.
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Old 20th May 2019, 04:56
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A good rule of thumb is your altitude in fpm

So 10,000fpm at 10,000ft

5000fpm at 5000.

1000fmp at 1000 etc.

Some airlines have 5000fpm to 5000 etc, but with speed brake and a high IAS this is easily breached.

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Old 20th May 2019, 05:11
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Some airlines have 5000fpm to 5000 etc, but with speed brake and a high IAS this is easily breached.
Gobbo, I don't know what leadsled you fly, but that sounds ridiculous. First, you'd be doing 250KIAS max in G below 10, and I very much doubt you'd get anywhere near "easily breached" 5,000fpm even with full boards in an "airliner". Even I would be puckering at 5,000fpm below 10k, let alone approaching 5,000ft AGL.
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Old 20th May 2019, 05:32
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Every tried an emergency descent

Got 10,000 fpm going into Glasgow and Gibraltar on trident 1s with reverse and brakes but my best was positioning a F100 into Fumicino were I saw 16,700 fpm before I chickened out..fair bit below VNE..recon 20,000 was attainable. Happy days when a captain was a captain and could fly an aircraft manually.
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Old 20th May 2019, 05:54
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Originally Posted by Capn Bloggs View Post
Gobbo, I don't know what leadsled you fly, but that sounds ridiculous. First, you'd be doing 250KIAS max in G below 10, and I very much doubt you'd get anywhere near "easily breached" 5,000fpm even with full boards in an "airliner". Even I would be puckering at 5,000fpm below 10k, let alone approaching 5,000ft AGL.
I agree Bloggsy, complete nonsense!
The thread poster said class G with no mention of pressurised or unpresurized but no Airline machine is going to be doing a high ROD in that environment OCTA neither would a basic GA plane due comfort . There's lots to consider, EPGWS/TAWS etc. Normal Vnav's go down at approx 2500fpm and if programmed correct there's no need for an excessive ROD unless traffic or ATC restrict normal Ops. Airline SOP's also have restrictions during the last 1000 ft. Add in body angle etc there's really no need for it.
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Old 20th May 2019, 06:02
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Capn Bloggs - In the baby Citation, we're normally 2-3000 but 4-5000 is needed occasionally and is no great drama - and that's at M.63 into 250. The bigger Citations, Lears, and airliners might be comfortable at double our FPM.
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Old 20th May 2019, 06:17
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Originally Posted by machtuk View Post
Under normal Ops 500' ROD for comfort, anything higher is unusual.
That's a good rate for the cabin - not the aircraft.

Back in my skydiving days, objective was to be back on the ground before the tandems landed. Easy in a PAC, bit harder in a 206.

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Old 20th May 2019, 08:22
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Over 1000 fpm unpressurised, I find people start getting aware of their ears............Also instructors start sweating.

1000+ OK for seconds in a good sideslip to renovate an approach.

My planning figure is 500fpm for no good reason.
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Old 20th May 2019, 08:55
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Originally Posted by Sunfish View Post
Over 1000 fpm unpressurised, I find people start getting aware of their ears............Also instructors start sweating.

1000+ OK for seconds in a good sideslip to renovate an approach.

My planning figure is 500fpm for no good reason.

You need a pressurized aircraft
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Old 20th May 2019, 11:15
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500FPM for unpressurized piston twins (AC50/PA31/PA34) is easy on the ears and seems to keep me nicely in (or out, as required) the control steps and sets up for an easy approach, allowing time for speed management (gear/flap) and engine temps.

Pressurised piston ops (601P) are a little different, but still 1000-1500 is pretty good, the cabin can keep 500 or less at that speed, and still gives you plenty of options for speed control and doesnít have you in the yellow arc when itís bumpy.

Adding a ROD/ROC restriction would be a pain in the a$$ and add another consideration to your approach that isnít really needed.

As for skydiving, isnít it get down as quick as you think you can get away with without tearing the wings off‽??
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Old 20th May 2019, 12:31
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Some years ago a skydiver driver told me he descends at VNE indicated all the way down to circuit height.......I just shook my head and kept an eye on the news,
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Old 20th May 2019, 12:48
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Bloggs, a bus will easily pull over 5000fpm with full boards at 250kts, especially if youíve slowed for whatever reason, say to green dot, then wind it back to 250 and pull out the brake.

If you pull speed at 190kts with flap 2 and brake/open descent, itíll do it too.

If youíre silly enough to be in expedite descent below 10 with 1/2 brake, youíll be pulling 6-7000fpm.


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Old 20th May 2019, 13:12
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Originally Posted by The Green Goblin View Post
A good rule of thumb is your altitude in fpm

So 10,000fpm at 10,000ft

5000fpm at 5000.

1000fmp at 1000 etc.

Some airlines have 5000fpm to 5000 etc, but with speed brake and a high IAS this is easily breached.

Dude you couldn't even do that in a King Air.
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