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35

The majority of the heat developed during reentry of a space-vehicle comes from air compression not friction. Remember, to go into space, you don't have to go very high, but to orbit you will have to go very very fast, and it's not the fall that produces the heat, it's the slowing down part. If you had a human fall without a chute, the terminal velocity (...


32

Qualification: I worked at a sport parachute center as an instructor for 10 years and I hold an FAA Master Parachute Rigger certificate. I believe that qualifies me as an expert on the subject. The fastest a human can fall unassisted is about 300km/h (head-down dive). Far too slow for frictional or compressive heating. Fighter pilots have ejected at ...


27

Puzzled by this question I did my own research and found numbers that allows to get a good comparison for year 2016: According to the United States Parachute Association (USPA), there were 3.2 million jumps in 2016 and 21 fatalities. Therefore, the chances of dying in a single jump were 1 in 152,381. For a comparison with driving, we can use data from the ...


20

You should descend in a controlled way, taking into account that your descent rate should be ≤ 29 mph (less than 13 m/s), once below 2,500 feet. If the descent rate is higher than that, then there is a risk of the AAD popping the skydiver's reserve parachute, mid-flight.


20

It is not legal to conduct skydiving into clouds, atleast in US. From 14 CFR §105.17 Flight visibility and clearance from cloud requirements: No person may conduct a parachute operation, and no pilot in command of an aircraft may allow a parachute operation to be conducted from that aircraft— (a) Into or through a cloud, or (b) When the flight ...


18

Qualifier: I am a master parachute rigger. The bag serves two functions - it allows the suspension lines to straighten out in a controlled manner, and it prevents the canopy from inflating before the lines are fully stretched out. It is not always required - people who want a very fast opening can pack without a bag, I have done this many times myself. ...


16

Is it legal? No. Skydiving is a VFR operation, FAA regulations ( assuming the USA ) clearly say no jumping through clouds. Few jump planes are IFR equipped to get up there anyway. Is it safe? Yes. Done it plenty of times myself on partly overcast days. The chances of hitting another aircraft in freefall are miniscule, and skydivers basically have no chance ...


12

14 CFR 105 covers parachute operations in the USA. There is not a requirement for a NOTAM, but since this happened at an uncontrolled airport the nearest ATC facility must be notified at least 1 hour in advance but not more than 24 hours in advance and, they must have approval from airport management. Then for the actual jump, ATC must be notified at least ...


11

Qualifier: I am a master parachute rigger and taught sport skydiving for 10 years. Standard jump altitude is 12,000 feet AGL - this is one turn of the standard parachutist's altimeter. This height provides 1 minute of freefall, is within reach of a Cessna with a decent engine and does not require supplementary oxygen. For most places, this means an ...


11

Here is another way to understand risk perception in skydiving vs driving. In skydiving, equipment malfunction is the cause of 50% of deaths. The highly regulated automobile industry would never stand for this. It would be deemed unnecessary and engineered out of the products. Collisions, landing problems, and other account for the other 50%. In driving, ...


10

Skydiving flights are abusive on engines for a number of reasons, but it's all tied to the fact that these flights are all about getting up to altitude, kicking the jumpers out, and putting the plane back on the ground as fast as possible so you can pick up the next group and do it all again, as many times as possible in a day. While all skydiving descents ...


9

There is a spring-loaded backup chute that will auto-deploy when the jumper goes too fast and is below 2.5k feet. If that also fails, the jumper becomes a smear on the ground. Freefall speed (aka terminal velocity) is not fast enough to start any type of burn.


8

is there anything I as a passenger can do to improve the safety of the flight You should do exactly what your told, when your told and make sure you keep well clear of spinning propellers. You will have a marshall or the pilot themselves guiding you when airside - do exactly as you're told! what pre-flight checks should the pilot make before taking-off ...


7

If they are unlucky enough to have a failure to deploy the parachute: They will probably hit the ground at approx 190 Km/h (120 Mph) in one piece. The unfortunate victim will most probably die instantly.


7

Because they tend to climb quickly to get to jump altitude (high power, hot engine) then descend very quickly to pick up the next batch of sky divers. Time = money. Close the throttle, point the nose at the landing site. However paul indicates in the comments that he worked at a centre where they took this into account and exercised caution (good ...


6

You didn't mention any particular country, but for the US I found an NTSB report called On the Safety of Parachute Jump Operations. It's from 2008 so some of it may be dated, but it says that no reliable data exist (emphasis mine): According to USPA safety records, from 1992 through 2007, about 30 parachutists per year were killed in jumping mishaps. ...


6

As paul mentioned, "standard" altitudes for sport skydiving facilities near sea level are in the 10,500-13,500 AGL range. Dropzones significantly above sea level typically either reduce their jump height to stay under 15,000 MSL or provide supplemental oxygen in the plane and go up to 18,000 MSL. Many dropzones will offer jumps from 18,000 MSL for an ...


5

Answer based on information found on-line. Related documentation: USAF C-130 Operations Procedures C-130T Flight Manual Lockheed News Service, 1957 KC-130 Specifications KC-130J Specifications C-130 HALO Practices C-130J Hercules Source: Flight Global The KC-130 Hercules is the tanker variant of the C-130 Hercules. The cargo opening consists of a door, ...


4

I'm a USPA AFF, tandem, and static line instructor. Your signed and completed A-License Proficiency Card is valid and USPA will process it without the stamp. You only need the stamp if you want to go to another dropzone and use your card as a temporary license. The proficiency card is only valid for 60 days after the date it was completed, so don't waste ...


4

Short answer: you need a commercial pilot's license. The drop zone will provide the extra training, it takes about a day (I worked at a skydive center for 10 years) However, since you seem to not have any kind of pilot's license right now (or you would know this already) I will add that it isn't a full-time job at any except the busiest drop zones. Our ...


4

The aircraft in the referenced video showing a very rapid descent is a King Air (or similar). Turbine aircraft really don't have shock cooling issues - standard procedure is engines to flight idle, props to flat pitch, nose down to Vne. Planes like a Pilatus Porter can descend faster than freefalling jumpers and are often used as extras in films (you need to ...


4

I wouldn't call it a "descent mode from altitude". It's considered to be a dangerous and foolish practice to operate an engine in ground beta (generally coming back into DISCING - blades flat) while in flight to get steep descent rates. If the prop doesn't want to come out of ground beta, you are dead meat. When the Twin Otter was in production, it was ...


4

I'm an ex jumper and I'd say the two major risks in a skydiving airplane ride are engine failure on take off or while too low to bail out, and a canopy deployment out an open door while in flight. If you're in a piston engine Cessna 206 and the engine quits at 200 feet and there isn't lots of runway still out front, it's gonna hurt. If you're in a piston ...


3

One thing to look (not just for this, but for with all aspects of aviation) is evidence of a Safety Culture. A skydiving operation is no different. Skybrary defines Safety Culture as follows: Safety Culture is the way safety is perceived, valued and prioritised in an organisation. It reflects the real commitment to safety at all levels in the ...


3

If there's such a thing as a standard maximum altitude for sport parachuting, the best answer would be 15,000' MSL, as above this CFR 91.211 requires supplemental oxygen for all passengers - and providing this to sport jumpers would be an expensive nuisance. Note that this does not vary with ground elevation - so indeed jumpers in the Denver area will not ...


2

Shock cooling is not a problem in reciprocating aircraft engines. In fact, today you almost only hear it mentioned in the context of turbocharged aircraft, and even then to avoid shock cooling of the turbocharger. Another common misconception. You'll find no mention of shock cooling in the Pilot's Operating Handbook. http://www.avweb.com/news/pelican/...


2

Perhaps trivial, but your landing weight will be higher than during a standard run sans skydivers, which will have an impact on stall speed, landing distance etc.


2

I just came across this. AOPA is a reliable source but it is not a reference to a regulation. Beta mode is only available for ground operations. Many single-engine turboprops have low propeller ground clearances, so it is vital to minimize beta thrust in contaminated areas to avoid engine and prop damage from dirt and debris. A few creative pilots have ...


2

I found this FAA Working Group paper on it https://www.faa.gov/regulations_policies/rulemaking/committees/documents/media/taepiht14-112699.pdf (28 page paper, poorly scanned PDF, I am not copying any sections here.) It looks to me under the Recommendation section that are proposing putting the plane into beta just be made a seperate distinct action such ...


2

You jump with a main chute and a reserve chute. The odds for either one of these failing are roughly 1 in 1000. This give approx a 1:1,000,000 chance both fail and you fall to your death. That’s the risk of a parachute failure. It does not account for risks associated with jump plane crashes, mid air collisions during the ride up, free fall or canopy ...


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