AAD fire in a descending aircraft

[baronn 111]

how many have witnessed/seen this before?

[phoenixlpr 0]

baronn

how many have witnessed/seen this before?

Negative. I've landed with the plane 3-5 times in the recent years with Cypress2 active. No problem so far.

[DJL 232]

Yes. But never if the parameters of the particular AAD were not met for firing. This is about knowing what the equipment is supposed to do. What are the specifics of your question?

"I encourage all awesome dangerous behavior." - Jeffro Fincher

[jacketsdb23 45]

I've landed several times in a plane with a student over the past couple of years and each time I turn the AAD off. One time I wasn't able to get the Argus off, and that was the longest 2000 ' to landing strip ever.

Losers make excuses, Winners make it happen
God is Good
Beer is Great
Swoopers are crazy.

[Jbag 0]

hopefully the pilot is aware that some AADs might be active and slows his decent around 1500'.

IHYD

[JohnnyMarko 1]

Jbag

hopefully the pilot is aware that some AADs might be active and slows his decent around 1500'.

It was taught at my DZ that if you're riding the plane down, inform the pilot as well as tell him/her that you have an AAD.

[DSE 3]

Quote

It was taught at my DZ that if you're riding the plane down, inform the pilot as well as tell him/her that you have an AAD.

Hopefully this is taught at every dz. It's standard practice at the dropzone's where I've taught.

[billvon 2,391]

>how many have witnessed/seen this before?

It's very unusual with a Cypres. It would be very unusual to see an aircraft exceed 78mph (descent rate of 7000 feet per minute) while setting up for landing.

At one load at the World Team we saw several firings because the C130 pressurized unexpectedly - and since the pressure can rise very rapidly, the AAD interprets that as a rapid descent. On our aircraft we realized what was going on (rapid change in altimeter reading with a level deck) and we got them to stop before the pressure altitude reached 1000 feet.

I have, however, seen several FXC and Sentinel firings due to rapid descent. (Mostly due to JM error - we knew we had to shut those things off when descending.) Fortunately they aren't used much any more.

[skydiverek 54]

Student AADs have much lower fire speed. Only like 29 mph for Student Cypres. Easily acheivable in descending airplane.

[pchapman 261]

AAD fire in a descending aircraft?
If you are talking about "normal skydiver" ones, I don't recall hearing of cases. Student and pre-Cypres ones are the ones that tend to get set off by fast descending aircraft.

Somewhere in between are tandem settings:

Back in '06 a C-182 in Ontario got caught in haze and thunderstorm related weather, got a wee bit out of control, bent the wings/fuselage/tail, and popped one or two Tandem Cypreses, which needs 78 mph at 1900 ft. The plane and jumpers did pull out in time. (Who knows if the actual vertical speed was that high; it is possible that cabin pressure changes partially fooled the sensor. Still, the aircraft was in a very dangerous situation.)

[mr2mk1g 10]

I've seen a student cypres pop on two occasions because the instructor failed to talk to the pilot.

[fcajump 153]

mr2mk1g

I've seen a student cypres pop on two occasions because the instructor failed to talk to the pilot.

As a low-time pilot... I'm not sure why a jump plane should need to still be descending at 2400fpm (~28mph vertical) at/below pattern altitude (750' AGL)... Not to say they don't, but can Diverdriver or one of the others tell me if that's normal?

JW

Always remember that some clouds are harder than others...

[riggerrob 558]

Yes, I saw an FXC 8000 fire in my lap back when I was a freefall student .... back when chest-mounted reserves were still fashionable ... back when FXC 8000s were still in production.

We climbed above clouds, then could not find the DZ. After twenty minutes of rafting about, the pilot dove through a small
hole in the cloud layer. My reserve dumped into my lap. Good thing the door was closed.
Wphhhhhew!

A few young, hot-shot pilots enjoy exceeding the red-line as they dive through pattern altitude (1,000 feet above ground level). If they survive exceeding the red-line in new airplanes, they learn the wrong lesson, because they will not survive exceeding the red-line in airplanes older than themselves. Those hot-dog pilots don't last. Either they break airplanes or get fired. Lucky pilots move on to boring jobs flying airliners.

Properly-trained pilots know to descend gently when they have skydivers on board. Properly-trained pilots also fly predictable landing patterns slower than the red-line.

[df8m1 19]

baronn

how many have witnessed/seen this before?

What is the basis for your question?

[SStewart 13]

Multiple cypres fires (3) in a Cessna Caravan back in 2007. This incident happened when an AFF instructor and another experienced jumper decided to leave the students in the plane because of strong winds and thunderstorms. The instructor and his buddy jumped and during the decent the 3 students AADs went off, just seconds after one of them went to the back of the plane to shut the door. (because they were cold) The AADs were student mode. The AFF instructor had his ratings suspended by USPA.

It was decided that even though the students were cleared for solo free fall the instructor should have remained on board, turned off the AADs and seat belted the students. They landed without seatbelts on and 3 open reserves.

Onward and Upward!

[billvon 2,391]

>Student AADs have much lower fire speed. Only like 29 mph for Student Cypres.

Good point. Every place I have worked has used expert cypreses for students, so I often don't consider them.

[Gary73 8]

King Airs and some other turbine aircraft can definitely exceed Student AAD firing speeds during a routine descent. (29 MPH (2,550 feet/min)) at 1,000 feet. I've seen it happen several times. If you aren't sure that the AAD's turned off, do be sure that the pilot knows to slow the descent by 2,000 feet. This should be part of every turbine jump pilot's training.

"Extraordinary claims require extraordinary evidence." - Carl Sagan

[ChuckMartin 0]

I saw it happen to a entire load a few months ago. A group of military guys jumping at our DZ had to ride down and every cypress fired. The ADD's they were using are close to what a student one fires at. Not a lot of happy people at the airport that day.

[riggerrob 558]

Thanks for the reminder.
We discussed it this week with a local jump-pilot. He was grumbling about having to descend slowly all the way from 10,000 feet (when clouds interfered with jumping).
We reminded him that solo AADs are set to fire at 1,000 feet or lower, so all he has to do is fly a regular, predictable, polite landing pattern.
As for tandem AADs, we told him to sow his rate of descent before he reaches 2,000 feet.
This explanation left him with only 2 altitudes to remember.

[stayhigh 2]

I've seen two in 11 years. Both student cypress.

Bernie Sanders for President 2016

[diablopilot 2]

You know another option is to shut them off.

----------------------------------------------
You're not as good as you think you are. Seriously.

[piisfish 135]

Had 2 out of 3 AAD's fire in a descending truck. According to the manufacturer the AAD's exceeded firing speed

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[mxk 1]

piisfish

Had 2 out of 3 AAD's fire in a descending truck. According to the manufacturer the AAD's exceeded firing speed

Which AADs (fired and didn't fire), in which mode, and was the truck falling off a cliff?

[piisfish 135]

The 3 were same brand and model of AAD, and they were very transparent about the answer. So transparent it looked empty.

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[WV177RG 19]

"A few young, hot-shot pilots enjoy exceeding the red-line..."
Airspeed indicator redline is not the only limiting factor: structural failure can occur well below redline.

Two critical speed limitations are Va and Vno.
Va is design maneuvering speed. Va is NOT marked on the airspeed indicator. It changes with aircraft gross weight. Fly below Va for a given gross weight/loading and the aircraft will stall aerodynamically before reaching its design load limit, preventing structural damage. This provides a margin of structural protection in turbulence and during increased G loading maneuvers. (Yank and bank, etc.)

Vno is maximum structural cruising speed for PISTON powered aircraft (C-182, etc.) This is the border between green (normal) and yellow (caution) arcs on the airspeed indicator. Vno is based upon maximum certificated gross weight and resultant wing loading. We should only fly in the yellow arc in smooth air, and with no abrupt flight control inputs.

TURBINE powered aircraft (Twin Otter, etc.) ASI's typically have no yellow arc/Vno. Structural certification rules allowed us to operate up to redline (Vmo/Mmo--maximum operating speed/maximum mach operating speed) in normal regional airline service without undue concern over potential structural or flight control damage. Additionally, hitting airspeed redline due to gusts, etc., would trigger 1,000 cycle tone and red WARNING light, alerting us to reduce power and airspeed back to normal operating range. Light aircraft don't usually have these reminders.

Local Twin Otter pilot was notorious for deliberately exceeding aircraft limitations despite numerous pleas from pilots and jumpers to stop. Shortly after leaving for another dropzone, he induced aerodynamic flutter in flight controls and structural damage in his new employer's Otter after deliberately diving the airplane beyond its limitations. Lucky he wasn't killed.

Skydivers rely upon our jump pilots to provide safe transportation to (and sometimes from) altitude so we can enjoy this fabulous sport as safely as possible. A huge thank you and shout out to our Otter and Caravan pilots who flew four days of nonstop safe, efficient loads at our Skydive Pepperell Boogie concluded last night--great job guys!