Aircraft jumper capacity

[miconar 0]

Hi everybody!

I hope someone here can help me answer a question about aircraft capacity.

I find many common skydiving aircrafts are used to fly more jumpers then are specified as max passengers by flight manual or FAA, adhering to (I assume) maximum load and CG limits instead. Example beech99s are listed as 15-17 but I've seen 19 jumpers listed on them, Cessna 208 have up to 14 passengers with a waiver, but I know DZs that fly more jumpers then that in them.

Are jumpers passengers or cargo? What if anything do you need to legally fly jumpers based on lift capacity?

Thank you all!

[gowlerk 1,903]

Quote

Are jumpers passengers or cargo?

In Canada they are neither. They are "personnel essential to flight". The capacity of the aircraft depends on staying within its weight and balance limitations and the number of "parachutist restraints" (seatbelts) installed.

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[Elisha 1]

To further elaborate, the "max passengers" assumes actual seats in the plane. With sitting on the floor, straddle benches or fold down benches, these weigh a lot less than passenger seats, which take up much more space and weight.

[totter 2]

Hope this will clarify a little for you.

When you look at a standard aircraft, let's say a Caravan, you'll see that it has seating for 9 passengers plus two pilots. This was how the aircraft was certified by the FAA. The Type Certificate Data Sheet or TCDS.
The TCDS is basically the specifications that the manufacture states they'll build the aircraft to and it is approved by the FAA. The TCDS includes, not only max seating, but also type of engines, propellers, fuel type and load, CG ranges, Max gross weight, etc...
So now let's take the Caravan again. TCDS says its certified for 9 passengers or less. BUT your a DZ operator and you want to put 14 people in it. (14 is being used as example only). Can you legally do this?
YES, but with approval.
This approval comes in the for of a Form 337 or STC. Both are forms of alteration to the original TCDS
A Form 337 is a Major Repair or Alteration form used to gain approval thru a Field Approval. Field Aprroval meaning you just send the paperwork to the local FAA office (FSDO) and if the inspector is in a good mood they Approve the alteration for that specific aircraft.
An STC requires more hoops to jump thru, involves more of the FAA engineers, since it is more of a blanket alteration that may cover an entire aircraft group.
Using the Caravan, with let's say serial number 1, the Form 337 would cover only serial number 1.
But a STC could cover from serial number 1 thru serial number 2000. And not just the standard C208A but also the C208B Grand Caravan.

So let's get back to number of passengers;
You have a Caravan, want to put 14 jumpers in it.
First off the regulations allow for the removal of seats for the purpose of parachute jumping. So the term "seats" is out.
You lay out in your aircraft, using a seating chart and Weight/Balance form, the locations (Aircraft Stations for W/B purposes) exactly where the new seatbelt will be located for the 14 people.
You show that with different fuel loads, number of people (full loads, partial loads sitting all forward or aft) that the aircraft remains within the Max Gross Weight AND within the CG Limits as stated by the TCDS. [These numbers are none negotiable]
You then also submit as part of the paperwork the type of restraint that will be used [must be TSOd ( a whole different topic for discussion)], how the restraints will be attached to the aircraft, and any type of supplement seating, i.e. Straddle Benches.
All this goes to the FAA FSDO in Form 337 format and like I said, if the inspector is in a good mood and agrees with all your calculations and figures and his/her supervisor is in a good mood and agrees they will come and take a look at the aircraft as altered and if the aircraft matches the paperwork they approve the alteration to the TCDS with what is called a Field Approval.
This then allows you, the operator, to fly that one specific aircraft with 14 people.
You buy a second Caravan you have to go thru the whole process again, but this time you can use your first alteration as Approved Data and it make the process a little easier.
On the down side, if you have a FAA FSDO that is not open to the unknown, most FAA Inspectors know very little about skydiving mods so it scares them or they're just not in the mood for the extra work then they'll make you submit for an STC.
You do all the paperwork and Due Diligence for the STC, send it to the ACO (Aircraft Certification Office), they look at it and say "you just need to do a Form 337 for this, send it to the FSDO" and you are now part of how the US Governmemt system works. (Tongue in cheek)

Hope this answers any question, in the long format.

[riggerrob 558]

Agreeing with everything Gowlerk and totter said and elaborating on what Elisha said.
Many jump-planes carry more jumpers than the plane was originally certified for because they have been gutted and only carry partial fuel.

Gutted means removing components no longer needed for day VFR flight, including: de-icing boots, cabin pressurization, fancy upholstery, toilets, inflight kitchen, etc.

Many jump planes further reduce weight by rarely carrying more than 2 hours worth of fuel. For example, early Beechcraft King Airs have a total of 6 fuel tanks with one tank in each engine nacelle, plus 2 more tanks in each outer wing panel. Since they only need nacelle tanks for flying jumpers, many DZOs forget to fill the outer wing tanks all summer, then wonder why they dry out, crack and leak. Oh! Well! We weren't using the outer tanks anyways.

Cessna 172 - 3 jumpers
Cessna 180 and 182 - 4 or 5 jumpers
Cessna 205 and 206 - 6 jumpers
Beech 18 - 12 to 14 jumpers
DeHavilland Twin Otter - 19 to 24 jumper
Shorts Skyvan - about 20 jumpers

[WV177RG 19]

Our airline flew Twin Otters and Dornier 228s (Precision*/Eastern Express, later Northwest Airlink) in skydiving service on occasion. Certificated for 19 passengers and a crew of 2 pilots, the Dornier had a small jump door but climbed fast and had STOL--short takeoff and landing--capabilities. It was well-suited for it's mission of connecting passengers from small airports around the northeast and Quebec into major airports of the northeast corridor (BOS, LGA, JFK, PHL+) with its ability to depart from relatively short runways, maintain 190+ KIAS initial approach speeds to keep up with the heavy iron, throw out the anchor close in, make a short-field landing and clear the runway to facilitate close separation between arrivals and departures. Particularly exciting for passengers was our ability to land on RWY 33R at BOS: we could pass 747's on parallel approach to 33L, drop gear and flaps, flare a few feet up while still over the water, touchdown on the numbers and use only half the available 2,550'.

With the seats removed and jump door mod in place, the Dornier could accommodate 22 or 23 skydivers, IIRC. For a few years, pilots were given the option of taking a checkride for a single-pilot type rating, freeing up the copilot seat for jump ops. (My upgrade class was the first after our FSDO required two pilots for all operations, so my type rating contains the limitation "second-in-command required.")

When our airline was bankrupted by corporate raiders, the aircraft were sold and ferried to Africa. I heard some of our pilots served short term contracts flying jumpers for the Saudi government.

*same airline from the French King Bridge incident thread

[wolfriverjoe 1,340]

WV177RG

... Certificated for 19 passengers and a crew of 2 pilots...

One reason that the number "19" is popular for passenger capacity is because flight attendants aren't required for planes that carry 19 or less (depending on payload capacity).

FAR 121.391

"There are NO situations which do not call for a French Maid outfit." Lucky McSwervy

"~ya don't GET old by being weak & stupid!" - Airtwardo

[nolhtairt 0]

riggerrob

Agreeing with everything Gowlerk and totter said and elaborating on what Elisha said.
Many jump-planes carry more jumpers than the plane was originally certified for because they have been gutted and only carry partial fuel.

Gutted means removing components no longer needed for day VFR flight, including: de-icing boots, cabin pressurization, fancy upholstery, toilets, inflight kitchen, etc.

Many jump planes further reduce weight by rarely carrying more than 2 hours worth of fuel. For example, early Beechcraft King Airs have a total of 6 fuel tanks with one tank in each engine nacelle, plus 2 more tanks in each outer wing panel. Since they only need nacelle tanks for flying jumpers, many DZOs forget to fill the outer wing tanks all summer, then wonder why they dry out, crack and leak. Oh! Well! We weren't using the outer tanks anyways.

Cessna 172 - 3 jumpers
Cessna 180 and 182 - 4 or 5 jumpers
Cessna 205 and 206 - 6 jumpers
Beech 18 - 12 to 14 jumpers
DeHavilland Twin Otter - 19 to 24 jumper
Shorts Skyvan - about 20 jumpers

Two types of Cessna 182's - standard body, no more than 4 jumpers, and wide body - up to 5 jumpers depending on total weight and sizes

[miconar 0]

Thank you all very very much! Especially Totter for the detailed explanation :-)

[frontfloater 0]

At my old dropzone, Sunderland in the UK, we set the club formation record in the early 80s by doing what was probably the world's first ever 8-way out of a 6-place Cessna 207 (unless you know differently...)

It began with me asking a question of the pilot - how is the 6-person limit decided, when those 6 people could weigh 200 pounds each, or 125 like me? His reply was that the 6-jumper limit was just an average, based on the aircraft's overall weight limit. So my next question was fairly obvious - if we weigh our two 4-way teams including all equipment, and it adds up to less than the aircraft limit, could we put 8 jumpers in? He said yes, in theory - but only if we could get those people far enough forward to not violate the CofG limit. Most jump planes in those days didn't have a red line, but that's what he was talking about.

So we got him to draw a line - then put our gear on and squashed everyone in. Most of us were light and fairly small, but it was still pretty tight and uncomfortable. One person was almost out of sight under the dash. But we did fit - so off we went.

It did take a LONG time to get to altitude, and we had to be careful on the run-in not to move too many people back at once, so it was a quick and strung-out exit. But we did it - the first 8-way over Sunderland. Some weeks later, someone overheard the BPA office staff dealing with our SCR & SCS applications say "Oh, have they bought an Islander at Sunderland?" Nope, we just used what we had to its maximum capacity - and as far as I know, didn't violate any FAI rules.

BOB

[tkhayes 124]

And I am not sure that it is even possible to take off with a Cessna 182, even with minimum fuel, with a pilot a 5 jumpers and stay inside of the gross weight limit.

Unless the jumpers and pilots are all Chinese acrobats or something like that. Lots of places do it, it is a great reliable aircraft that will fly well outside the weight limits, but actually doing the math for any given load on any given day? I bet it does not meet the mustard at all

DHC-6 with 22 jumpers and 4 loads of fuel on board is not much different. But planes fly. And history says it is not 'unsafe'. We had as many as 16-17 on a Beech 18 back in the 80's, 3300' ASL DZ too.... good thing the ground was flat prairie - you can hang in ground effect for a long long time waiting for that bit of lift..... airspeed is my friend.....

[Bob_Church 7]

tkhayes

And I am not sure that it is even possible to take off with a Cessna 182, even with minimum fuel, with a pilot a 5 jumpers and stay inside of the gross weight limit.

Unless the jumpers and pilots are all Chinese acrobats or something like that. Lots of places do it, it is a great reliable aircraft that will fly well outside the weight limits, but actually doing the math for any given load on any given day? I bet it does not meet the mustard at all

DHC-6 with 22 jumpers and 4 loads of fuel on board is not much different. But planes fly. And history says it is not 'unsafe'. We had as many as 16-17 on a Beech 18 back in the 80's, 3300' ASL DZ too.... good thing the ground was flat prairie - you can hang in ground effect for a long long time waiting for that bit of lift..... airspeed is my friend.....

But the 206, and i believe the 207 is similar, is sort of unique in that you can't overload it with jumpers. If you can squeeze another person in the aircraft can deal with it. The aircraft can. The jumpers, not so much.
I HATED 206 loads. I'd be nauseous by the time we got to altitude and there wasn't anything anywhere near like a comfortable position once you got six big guys and the pilot in it. And all those times you'd feel your stomach lift then hear that "thump" as too many people squeezed into the back too soon and it went down on its tail.

[gowlerk 1,903]

tkhayes

And I am not sure that it is even possible to take off with a Cessna 182, even with minimum fuel, with a pilot a 5 jumpers and stay inside of the gross weight limit.

Unless the jumpers and pilots are all Chinese acrobats or something like that. Lots of places do it, it is a great reliable aircraft that will fly well outside the weight limits, but actually doing the math for any given load on any given day? I bet it does not meet the mustard at all

DHC-6 with 22 jumpers and 4 loads of fuel on board is not much different. But planes fly. And history says it is not 'unsafe'. We had as many as 16-17 on a Beech 18 back in the 80's, 3300' ASL DZ too.... good thing the ground was flat prairie - you can hang in ground effect for a long long time waiting for that bit of lift..... airspeed is my friend.....

You can put 5 into a 182 if it has wingx s and the jumpers are smallish. But here in Canada TC will no longer allow enough seat belts for that many people. I think too many DZs were flying over weight. Flying overweight is unsafe. Even if the aircraft will climb just fine normally, if you have an engine failure outside of W&B limitations you will be in deep trouble very quickly.

[pchapman 261]

Edit: Ninjad by Gowler, who put pretty much my whole post into one sentence.

tkhayes

And I am not sure that it is even possible to take off with a Cessna 182, even with minimum fuel, with a pilot a 5 jumpers and stay inside of the gross weight limit.

TLDR:
I don't think it's that bad. Maybe not with a typical 182, I dunno. Some varieties in service could do it fairly regularly, although admittedly with maybe a little looking the other way about actual vs. theoretical jumper weights.


Details:

Is it that bad?
I've seen it where the numbers are good enough to make it legal looking even in a Transport Canada environment where at the DZ every load's weight has to be calculated and retained.

However, there may be a bit of over optimistic grey area left for the gear weights. And I personally don't know if oil weight for example was properly included, although it should have been. (Empty vs. operational empty weight)

Also, there are all sorts of C-182 variants so that can make a big difference in what is possible.

My example:
I've been at a DZ where the mid to late 1960s C-182s had a 2950 lb gross, using the Wing-X mods, and empty weights (of some form) usually just under 1700. The earlier planes tended to be lighter but the mods gave them the higher gross weight of later models. They were pretty stripped out as is common.

(And the aircraft were wide bodied, with most upgraded to 260 not 230 hp, so one could fit in and they climbed well enough.)

So we have 2950, minus 1700, take away 108 lbs for 18 gal fuel, 200 lbs for pilot and chute, 20 lbs for each jumper's gear (yeah, that's a little optimistic!), and one is left with 168 lbs per jumper. We used 170 as the baseline, modified depending on the particular pilot's weight. If the plane had already done a static line load, there was still fuel for one high load with a little more weight. (Although I haven't calculated reserve & unusable fuel.)

So loads were split about 50/50 between 4 and 5 jumpers, depending on whether it was skinny jumpers or some solidly built boys on the load. Two tandems and a one cam flyer was common too.

Admittedly it was overlooking things a little on gear weight, including clothing, cameras, weight belts.... But it didn't seem near impossible to be legal with 5 jumpers.

[billvon 2,380]

Quote

But the 206, and i believe the 207 is similar, is sort of unique in that you can't overload it with jumpers. If you can squeeze another person in the aircraft can deal with it. The aircraft can. The jumpers, not so much.

Right. But the aircraft is still overloaded per the mfr's specs. Most of the aircraft we use are very forgiving and have a significant performance margin, which is why we so often get away with it. But combine a hot humid day with a lot of heavy jumpers and a recently fueled aircraft and you can have trouble.

About 20 years ago I was bored and actually went through and did the W+B calculations on our old Beech 99. When we were at capacity you had to assume that everyone weighed 155 lbs - with gear - to be within limits during a normal load after refueling. (Airlines often use 170lbs as an average.) After that we didn't do any W+B calculations.

[Bob_Church 7]

"Right. But the aircraft is still overloaded per the mfr's specs."

What are those specs? They must be different from what I was told.
According to AOPA

"Ask 205/206 owners why they were drawn to such ordinary-looking airplanes, and the answer will nearly always center on load-hauling capability. Both airplanes have generous weight and balance limitations, and generally, filling the seats will not require an hour's worth of calculator time to keep the airplane in the envelope. With a useful load of 1,500 to 1,800 lbs. depending on the model, the aircraft competes with most other heavy singles and many light twins. "

The result being that you can't put more skydivers into a 206 than it can carry.

[riggerrob 558]

...... 206 loads. ....... And all those times you'd feel your stomach lift then hear that "thump" as too many people squeezed into the back too soon and it went down on its tail.
————————————————————————-
I HATE that sound! Even though I only heard it once when we stuffed 7 guys into a 206.
The longest-lived jump-planes are those with the widest margins of error.

If you think over-loaded airplanes climb slowly, you will enjoy their stall characteristics even less when they are unbalanced!
For some silly reason, they always told me to lean over the pilots’ shoulders when the Beech 18 took off????????

[billvon 2,380]

>What are those specs?

From Cessna website for the U206:

Max TO - 3300lbs
Empty weight - 1760lbs

Typical fueling (per Diverdriver website) - 40 gallons, 3 loads

Remaining usable load - 1288 lbs

With 5 jumpers + pilot - average weight must be below 214 lbs
With 6 jumpers + pilot - average weight must be below 184 lbs

Average weight used by the FAA for passengers is 170 lbs. So add 30 lbs of gear and you are at 200 lbs per person average.

So for 5 jumpers you are _usually_ OK - but perhaps not if you have a tandem load with two big TM's.

For 6 jumpers you are usually going to be overweight unless you have an STC that allows you to carry more weight (or are doing a women's record or something.) Note that in many cases STC's to add in-flight doors account for the removal of the weight of the seats and existing door.

>The result being that you can't put more skydivers into a 206 than it can carry.

Again, the aircraft will almost always get off the ground - there's a lot of margin built in there. But you can easily put more skydivers in than the plane can _legally_ carry.