Quick and Easy Helicopter Pilot Training
 

Contact a guy named Tank. You'll find him somewhere in the Matrix. He has training programs for all types of helicopter.

Give him a ring and ask for a "Pilot Training Program for the B412 helicopter".

In 30 seconds all the knowledge you need to be able to fly the helicopter will be uploaded to your brain via the telephone network!

Clever, eh?!

MMMM... WE MEET AGAIN "MR ANDERSON" or should i say Neo...

Hi,

Do you want any manual in particular or just the Flight Manual?

I bought a flight manual on CD ROM from a guy in Toronto on EBay. He had a whole selection of manuals copied onto CDROM. I can't guarantee it was legal, but he had his own business that specialised in that so I can only assume it was legit. If not, I'm sure Bell are onto him.

I did the usual Ebay thing and I had it in my grubby little hands in 10 days.

Do a google search or a search on ebay for flight manuals or pilot operating handbooks.

If you don't have any luck, PM me and I'll see if I can dig it up and give you more info.

Cheers
CB

Con...roger that thanks mate i will give it a go, and basiscally i'm trying to get a training manual on the a/c to start with....I can get my grubby hands on a " fright manual" at work. but the disk copies sound kool:ok:

Skitso,
Look I do have an acrobat copy of the FS 412 manual, I scanned the latest version and its on disk, saves lugging the two books about when on trips. However the files are rather large and not any good to send over the Internet, too slow and costly from my backwater of the unknown world. However if you want to PM me maybe we can sort an alternative.
Outhouse

412 ground resonance
 

Did you ever hear of a ground resonance incident in a 412?

I've done a search in the ntsb site without results.


Thanks
Aser

Aser - Your havent been bouncing the Malta Gozo machine have you :confused:

In the absence of drag dampers, undercarriage oleos or pneumatic tyres, it would seem unlikely to be a problem.

But the RFM does make mention of it....something to do with the ability of the skids to slip in the rubber mounts or something as I recall....thus setting up a lateral input to the rotor system similar to an oleo.

The Aft cross tube on the 412 has a support beam fitted not fitted to the 205 and 212, to give a single point attachment to the airframe to counter ground resonance if the elastomeric dampers sticks (fails) in the leading or laging mode. Thats what gives the 412 its rock from side to side when you move around on top the aircraft as the cross tube rolls within the support beam.

It's not unusual for a perfectly tracked and balanced 412 to 'pad' markedly on the ground at min collective pitch, particularly on concrete. Whilst it may be uncomfortable it is not divergent and can be stopped by raising the collective slightly.

idle stop I know what you are talking about, I had the experience in one 412 and I thought it was going to self destroy
:}

I believe the possibility of ground resonance in a 412 although very remote , exists.
The dampers , rubber in the crosstube, or one drop restrainer not in locked position after the previous shutdown... something can fail.
Maybe a pilot react intending to lift the helicopter and find himself hitting a nearby tree... ? :E
What do you think guys?
Ned-Air2Air: The machine is fine , I was just speculating about something I heard...

Thanks for your responses

In early stages of vertical bounce, place cyclic right aft, if this does not work as it often will, pull a little collective as was suggested earlier. Be aware that you can increase the bounce if you hold the collective tightly causing it to have a pilot induced factor as well , Cheers Yabu

Yabu

I would imagine if you pull the cyclic 'right aft' then your early stages of vertical bounce may well be replaced by broken tail rotor;)

As all Bell 412 pilots know - those things LEAK with oil underneath. The rubber dampers on the aft crosstube gets hammered by this oil and can eat them away fairly quickly.

This can increase the ground bounce as well.

I have never had anything close to ground resonance in the aircraft in over 1000 hours of flying them. :)

Spanish Waltzer, Moving the cyclic right aft is not to be read as a harsh manuever, and you will normally find a "sweet spot" at which time early stages of bounce will cease. I am only trying to aid, with my 4000 hours on the 412. If you think it is not a reasonable suggestion, then so be it. Regards

Yabu, right and aft is where usually I move the stick to turn off the Cyc Center light, so what you are suggesting in finding the sweet spot sounds like a good idea , I was taught just to add a little bit of collective.

Best regards.
Aser

Ground resonance is a term we misuse the way we misuse LTE and Settling with power. Every time a guy runs close to pedal limits he calls LTE, every time he starts falling through on approach it is VRS and every time the aircraft wiggles on the ground it is ground resonance.

Some thoughts on true ground resonance:

1) It is possible to get it in any aircraft that has a lag degree of freedom, even the 412.

2) It takes something mis-adjusted or mis-maintained to get it, because all helos that have lag hinges have systems to quell it. Manufacturers have to prove they are immune to ground resonance to themselves and to the FAA. Those systems (oleos, dampers on skids, dampers on blades, elastomers on all the previous) do not cause ground resonance, they prevent it.

3) It is a destructive resonance where the blade goes out of lag position, and the ground restraint (gear, skids, chocks/chains) reflects the out of balance back to the rotor in such a way as to drive the blade further away from the center. This means the vibration amplifies with each cycle.

4) True ground resonance is fast, vicious and destructive. Usually the number of cycles is few (maybe 10 seconds) and the cure is to leap airborne (stops the ground from reflecting the wave back to the head) or shut down fast, slapping on the rotor brake (which drives all the blades forward and again breaks the cycle).

5) Some helos have spots where the main rotor dampers are less effective (sweet spots in the cyclic) while on the ground, and they shuffle or bounce in yaw, roll or pitch enough to be noticed by the crew. These areas of lower damping are not ground resonance.

Nick

I think the point that everyone has been talking about with the last few replies was in conjunction with the "Ground Bounce" (not ground resonance) which can feel a little harsh dependant on the track and balance of the particular aircraft, wind direction, quality of dampers on the rear crosstube, etc.

:}

Oogle,
Agreed! You can get it in a BlackHawk at very aft stick, for instance, when you land down-slope. It is a combination of dampers that are stroking alot, tail wheel lateral compliance and AFCS activity.

So to resume:

1- The 412 has the possibility of ground resonance as any other helo with lead-lag movement in the blades.In the first post I was looking for a previous incident without luck.

2- The replies derived to the 412 well known Ground Bouncing capability :}

3- Nick: This is something... I was missing, I was thinking that a blade with a bad lead-lag damper will develop the ground resonance, but not, it's there just to preven it, Thanks.

Best regards.
Aser
;)

I agree that generally with the 412 we are talking bounce which is not resonance. Both cyclic position, and to a larger degree some addition of collective will help. We have found the bounce can become quite a thump particulary on wooden wellheads, where some movement of the deck allows the situation to worsen. In cases like these pilots do tend to hold the collective tightly and while they bounce, unconciously bounce the collective as well increasing the effect. I personally have not heard of this developing into resonance as such, but it does get your attention for sure. Some good technical feedback on this has come thru, Thanks guys.

Many of the 412's I have gound run have been prone to some form of bouncing. It has always happened on concrete and starts at about 95%+ with min pitch. Invariably the aircraft has been lightly loaded (empty actually). Certainly there was the thought that this could develop into full ground reasonance if it were allowed to continue Raising the collective slightly seems to be the cure. It was very uncomfortable and I am not able to say whether the condition is divergent, or not.

I have never experienced this problem on either a B212 or a B205 although I have experienced collective bounce on a B205. The situation there was a gentle run on on a bank of shells/stones caused by insufficient friction on the collective.

Hope this helps.

NC43

412 operating costs
 

Hi guys,

I've got the manufacturer's and 'blue book' type costs but can a couple of you give me some real world gen on operating costs for 212/412 in harsh(ish) desert environment but with hangar and daily maintenance available doing pax and equipment transfer with one to two hour flights, 100 hours a month - minimal sling, no high cycles, nothing unusual ?

Eg. real maintenance, unplanned spares, fuel, oil, blades etc.

Thanks,

G7

Go with Conklin and D's estimates and you will do more than well, the 412/212 has no surprises.

The desert should not pose any problem for the 212/412 its one of the most dependable aircraft this world and its surroundings have available for you to make money with it.

Thanks, we got those.

Recent newsletter reckons US$ 606 per hour for 412 then ?

Came to this somewhat late, but why not jump in anyway!

IME the 412 ground bounce is usually caused by track/balance problems, and can't always be eliminated no matter how long you try. I've seen it caused by a t/r imbalance. We worked on the m/r track/balance for weeks, with no success in lowering the ground bounce. Then when the t/r balance was done as part of the scheduled maintenance, it was found to be well out of tolerance, and when balanced the ground bounce was gone.

It's a miracle when a 412 has no vibrations anyway, considering that it starts out with the blades in different planes. Sometimes you just have to live with a ground bounce, but I try to get it tracked out. Raising the collective slightly usually helps, as already mentioned.

412 Ep Hp Sp
 

What is the difference in performance and structure between these 412 versions? Is there any other that i might not know about?

J

How much time have you got :-)
Engines are different across the 3 models, although engine models are sometimes common between SP/HP (-3BE/BF/BG), and between HP/EP (-3D). SP uses 212 tail rotor driveshafts with driveshaft clamps. HP/EP uses Thomas Couplings on the tailrotor driveshafts. HP/EP have ITT trim for Engine #2, SP has the 212 setup. EP has different Damper Bridges on the Main Rotor Head, but I think this can be retrofitted back to HP/SP. EP cannot fly with older style Damper Bridges though. EP measures rotor torque at the Main Rotor Shaft output to the Main Rotor Head. SP measure at the MGB input from the engines. Structurally, from memory, they are the same. Components are upgraded for each successive model, and engine horsepower increases with each model to hide the fact that the later models are heavier :-)
As far as perfomance goes, you'd have to speak to a driver.

noooby

Quite right except both the HP and EP have mast torque wich uses mast twist to determine torque with a lot more accuracy than the "No P" and SP wich totalize the torquemeter from eng #1 & #2 as on the Bell 212.

The "412 No P" or "412 Straight" or "412 Classic" how ever you want to call it, is structurally very close to the Bell 212 not having the aft center fuel cell (five fuel cells in lieu of 10).

Does anyone care to discuss the fuel system and how it works?:uhoh:

Yes, the Bell fuel system!!
Well it's not that bad ,to start with the 412 Classic is basically the same as the 205 and 212 fuel system with 5 main tanks giving approx 1450lbs fuel.
The 412 SP/HP/EP, has a ten tank system 6 floor tanks, with fwd, centre and aft floor tanks on each side, the centre and aft tanks take the same space as the 2 floor tanks in the 205 /212/ 412Classic with the fwd tanks fitting into the floor cavity behind the pilots seats.
3 of the 4 aft tanks are the same as the 205 /212/ 412 Classic with the extra tank befind situated in the rear hellhole area. With the fuel system extended fwd and rear in the airframe longitudinal CofG became a problem , so Bell came up with a series of stand pipes and valves to keep the CofG move to a minimum (a total move of approx 4 ". between 136.0 -140.0)
To do this Bell do it in a series of 6 "Burns"
Burn 1 is approx the top 1/4 of the 4 rear tank as the flow into the floor tanks
Burn 2 is the centre floor tank on each
Burn 3 the next 1/4 of the aft 4 tanks
Burn 4 is the fwd floor tank on each side (approx 800lbs left at end of burn 4)
Burn 5 last 1/2 (rest) of 4 aft tanks
Burn 6 remaining fuel in aft floor tanks.
Hope that helps and isn't too confusing, it had me stuffed to when i first did the course!!

Oh yeah and the main reason for the fuel system change?
More fuel Classic 1450lbs approx 225 nm
SP/HP/EP 2150lbs approx 350nm

Simple really!!!! :) Until the underfloor Jet Pump clogs or fails and you find that you can't get fuel out of the center underfloor tank!! DOH!! Stoopid stoopid stooopid system. But hey, that's the price you pay for continually modifying a UH-1!!! :eek:

Its not that bad the fwd floor tanks on each side and centre floor tanks on each side are conected together by the standpipe interconect to maintain even fuel on each side and you have the interconnect valve on the rear floor tanks and crossfeed after the pumps so you can still get justabout all your fuel if a jetpump or boost pump fail !
If you want to see a sh1t fuel system just look at the Super Puma ,7 tanks, no direct crossfeed to the engines and only a mickey mouse "crossfeed" pump between tanks if it fails and the crew don't monitor the fuel levels between sides you have the potential of running fuel out on one engine and still having heaps to the other engine , this has disastrous potential if you are running a long range internal tank as it only feeds into one side!! not so in a Bell!

Thanks guys. Only one info is puzzeling me. What does SP/HP/EP stand for exactly? The more i ask, the more different explanations i get :confused:

SP-Special Performance
HP-High Performance
EP-Extra Performance

In my Flight Safety manual it shows the following infor:

PT6T-3B PT6T-3D
100%Torque Twin engine torque limit

1800 SHP !800 SHP

Continuous Twin engine Torque limit

1600 SHP 1600 SHP

Continuous OEI Torque Limit

970 SHP 970 SHP
765 C ITT 820 C ITT

30 minute OEI ITT Limit

970 SHP none
822 C ITT
2.5 minute OEI ITT LIMIT

1025 SHP 1100 SHP
850 C ITT 925 C ITT


Hope this helps

Thank you all. That should do it.

Not that its important, but I think the correct designation for EP is Enhanced performance.

NSW Police to purchase 412's
 

Any truth that the NSW Police are going to purchase 412's to replace their aging AStar fleet