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BELL 412 IN THE MOUNTAINS

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BELL 412 IN THE MOUNTAINS

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Old 13th Jun 2018, 04:09
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BELL 412 IN THE MOUNTAINS

Greetings!

The 412 has proved its utility globally & i am sure that this thread will elicit several replies.
We are operating a 412 in the hills & mountains of North East India. The landing sites range from 500' upto 6500' AMSL.

I am personally curious as to what is the best approach technique for high altitude helipads:

1. Should it be a very flat approach? If yes, the pros & cons of it.
2. Should the approach be made with a say 5-7 degree glide slope? Pros & Cons.
3. In case of strong winds, should the approach become steeper? Consequences in case the winds suddenly die down (as they are prone to in hills).
4. Procedures for ensuring a safe and well controlled approach to a helipad.

Thank you.

Readers are invited to post replies directly to me email [email protected], if you so desire.

Thank you all.

Happy Landings!
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Old 13th Jun 2018, 07:13
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First of all, let me say one thing:

You should not fly in mountaineous terrain if you haven´t been trained to do so in the past by qualified instructors!
I spent a fair amount of my time flying in mountains and at high altitude, doing slinging, long line, Search and Rescue as well as Passenger transport, and have seen to many pilots flying there without proper training....which is deadly, there is no grey area on this.

Second, you will need to know the wind situation, and the power reserve for each approach-you need to approach in a way that allows you to always abort the approach and have a safe escape path, or to continue the approach should one engine fail.

In your example i would suggest to approach steeper-than-normal; a 4-5 ° approach would be a "normal" approach-i would tend to more than 10° (but this is difficult to say without knowing the exact details of the landing site)..

My highest landings were only around 16-17000 feet....probably other guys here with more insight at higher landing sites?

This could give you a little bit of background:
FAA
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Old 13th Jun 2018, 08:59
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Firstly - hueyracer has put it very politely but the question remains "what are you doing in the mountains in a 412 with no training?"

Experience in a lighter twin and/or single would be a prerequisite before attempting things in a medium?

The FAA background is a start but you may find more relevant info here.
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Old 13th Jun 2018, 11:14
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.
As a downunder master of the high mountain used to say : Keep your tail rotor safe of the crowd !
.
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Old 13th Jun 2018, 12:49
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...I wouldn't have thought 6500' was high altitude ops.
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Old 13th Jun 2018, 14:14
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...I wouldn't have thought 6500' was high altitude ops.
NE of India? 6500' pad could easily have a DA over 10,000' without much effort.
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Old 13th Jun 2018, 14:35
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Whirlybirdguy.

Your tone worries me. It sounds very 'un' technical and I suspect you have had very little if any formal mountain flying training - is that so?

If this is the case, nothing, no advice we give you will help because you will be completelty out of your depth as and when things go wrong.
Mountain flying is very unforgiving and as stated by RVDT, you could easily see yourself @ a Da of 10k and above.

Presumably your 412 is a semi rigid head? Whats the TRE like @ Hi DA?

Are you fully insured!!!
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Old 13th Jun 2018, 15:16
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If i remember correctly, there was a job offer somewhere on the internet a while ago...looking for experienced Bell 412 pilots with slinging and mountain experience....

I wonder why they never got back to the experienced pilots who applied for this.....

Honi soit quit mal y pense...
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Old 13th Jun 2018, 15:18
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Originally Posted by gulliBell View Post
...I wouldn't have thought 6500' was high altitude ops.
In Switzerland the CAA declared the limit at 1100 meters/3609 feet.

Landings above require high altitude training.
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Old 13th Jun 2018, 16:58
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Keep above the demarcation line and always aim for the upwind end of the feature.
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Old 13th Jun 2018, 17:19
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Whirlybirdguy. I would go to bell and do the mountain flying course you be amazed how much you learn get the boss to pay. Levo.
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Old 14th Jun 2018, 10:31
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Lightbulb

Originally Posted by whirlybirdguy View Post
Greetings!

The 412 has proved its utility globally & i am sure that this thread will elicit several replies.
We are operating a 412 in the hills & mountains of North East India. The landing sites range from 500' upto 6500' AMSL.

I am personally curious as to what is the best approach technique for high altitude helipads:

1. Should it be a very flat approach? If yes, the pros & cons of it.
2. Should the approach be made with a say 5-7 degree glide slope? Pros & Cons.
3. In case of strong winds, should the approach become steeper? Consequences in case the winds suddenly die down (as they are prone to in hills).
4. Procedures for ensuring a safe and well controlled approach to a helipad.

Thank you.

Readers are invited to post replies directly to me email [email protected], if you so desire.

Thank you all.

Happy Landings!
Crikey Mate...For Fvkz sake don't venture into the big hills without proper due training & someone to hold yer hand for a while India has rules for hill flying & without proper training (albeit average) You won't get a tick in the box to go

Anyways in reply to yer questions......
1. Firstly You should be very clear & confident what margin you have at the designated H height & what power margin You need to arrive & escape, well before committing to land keep Your approaches as flat as possible, or slightly climbing & don't loose ETL till the forward Rotor-Disc tip is almost over the front edge of your H. Pros; Safer to have no ROD, plus easier escape options. Cons: none
2. Keep Your approach angle well below 5º to minimise ROD & don't loose ETL during the final approach. Reasons...same as above in 1.
3. Unless going into a deep confined H absolutely DO NOT steepen Your approach just because there's wind, ROD increases which may not be possible to arrest? Yes some Mountain flying books & courses say steeper & vertical, but from personal experience having 1,000's of landing above 10,000' & a few hundred above 20,000' that is complete utter Bullocks, may work perfectly fine on a 500' even a 5,000' hill but when Your seriously up there, that is Bullocks to steepen any approach, unless the terrain gives no other option (& only then with extreme caution!)
4. That's a short book to write. A Mountain flying workshop I produced has a ground class of 1 full day with a minimum of 5 hours flying & that is the barest minimum I'd suggest You do to be only just safe! This question cannot be condensed & appropriately answered into a short paragraph here! In other words get some real Life training with someone who has serious real high Mountain time
5. Do everything into wind or on the power pedal side (except pee)

Happy Landings
VF
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Old 14th Jun 2018, 15:49
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Beware that unless you are configured for less than 9 pax, the HV curve is a limitation, not in the perfiotmance section, but in the limitations. Also look for a W-A _t Cgart.
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Old 18th Jun 2018, 14:20
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Dear ALL,

Thank you all for the wonderful posts & the amazing replies that this thread has elicited. Kindly note, my query was ONLY related for the Bell 412 & how the machine per se should be utilised. Personally, I have quite a rich experience in the mountains with extreme landings in the Siachen Glacier, at altitudes of 19500 feet and beyond on a regular basis.
Through this post, I was looking for issues & handling techniques unique to the Bell 412. In case anyone has anything on this, I would really be grateful for those inputs.

Once again, thank you all for your wonderful & informative contributions.

Regards & happy landings to all
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Old 19th Jun 2018, 05:20
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You should have specified this a bit more in the initial post....

What Bell 412 are you operating in this altitudes?
Classic, SP, HP, EP, EPI?

On high altitudes, the N1 and/or the ITT will reach the limit way before you will reach the torque limit-watch out for this.
(Not only applicable for the 412): Avoid rapid changes in the collective setting and/or fast controls in the cyclic or pedals, move controls smoothly.
Be aware of LTE-always land into wind.
Do not use the Autopilot (if installed) in ATT mode when operating in high altitude- The actuators will suffer, and will overcompensate.
Check your VNE and OAT-ALWAYS!
Keep your rate of D low, especially the higher you go....
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Old 19th Jun 2018, 09:09
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That's more like it - that's what PPRuNe is all about, obtaining practical sound advice - (almost) instantly.
Let's hope he's still around to read it!
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Old 23rd Jun 2018, 00:41
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Thumbs up

Originally Posted by hueyracer View Post
You should have specified this a bit more in the initial post....

What Bell 412 are you operating in this altitudes?
Classic, SP, HP, EP, EPI?

On high altitudes, the N1 and/or the ITT will reach the limit way before you will reach the torque limit-watch out for this.
(Not only applicable for the 412): Avoid rapid changes in the collective setting and/or fast controls in the cyclic or pedals, move controls smoothly.
Be aware of LTE-always land into wind.
Do not use the Autopilot (if installed) in ATT mode when operating in high altitude- The actuators will suffer, and will overcompensate.
Check your VNE and OAT-ALWAYS!
Keep your rate of D low, especially the higher you go....
Thank you Sir.
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Old 23rd Jun 2018, 00:42
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Dear All,

Thank you all once again for all your inputs. This thread is now closed. Happy Landings to all. God bless & God speed.

Regards

ajay
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