Three minutes? That is quick. Are there wait times after the first engine is started? When do the electronics come on prior to or after the first engine start?

Thanks

Hi WDE!

Is this Ontario EMS? We heard rumours about the a/c change/ upgrade. If it is Ontario, good for you guys.

As for dispatch times, I hope reference to flight manual/manufacturer's procedure is priority! I have come across the "scramble start" mentality on certain op's which leads to mission oriented mentality rather than solid aviation standards mentality!

Two minutes from engine start to airborne seems quite drastic. There must be some requirement for oil temperature and internal metals coming up to temp before placing any load on them??? Hope you 139 dudes can advise?

Cheers!

DK

Using normal battery start procedures, the second engine can be started as soon as the loadmeter is in the green (roughly 20-40 seconds). Using external power, the second engine can be started immediately after the first starter drops out (49% Ng). Using the Quick Start procedure, the second engine can be started after the starting engine Ng reaches 25%, even on a battery start. The only delay for any start is waiting for ENG & XMSN T's and P's. In our GoM environment, the temps are in the green very soon after the starter drops out. Colder climate operations would obviously have to wait longer. NOTE: No shortcuts here...These procedures are straight from the RFM.

As soon as the battery switches are turned on, all avionics are powered-up. There is a RAD MASTER switch that disables some of the avionics to aid in a battery start (RAD MASTER OFF). We use a GPU for nearly every start...RAD MASTER ON...and all avionics are powered-up as soon as the External Power is applied and battery switches are on.

Starts
 

And don't forget PW requirement to keep the difference in cycles between No 1 and 2 to less than 10%, means you need to alternate the first engine to be started, a little gem hidden away in the engine maintenance manuals and which I didn't find out until the first 50-hour check. Unlike Patniven, we're starting pretty much all the time on the battery so No 1 has been getting the vote all the time................................

heliski22

I'm a little confused, why not start the No 2 engine with the aircraft main battery?

All the best

Red

flungdung

I agree, but only connect the bus tie seconds before starting the No2. It's not been a hugh problem.


I admit that you don't get too many chances before the MAUs have got the better of the batteries, but that's par for the course with a 139.

Red

heliski22,
Did you try the DCL mode in the ils?

We have found that after reducing speed with IAS mode or using DCL mode, the helicopter always deviates to the right and we end aligned with the taxiway!
Agusta pilot also checked it.
Any other 4-axis user out there?

"Sunset"
http://i66.photobucket.com/albums/h2...P3120019-1.jpg

Regards
Aser

Aser I have noticed this in a few aircraft, however only on the 3 axis while using the auto level mode while reducing power on the ILS. As you spoke of it was quite a deviation to the right on the ILS.

I agree with Red white and blue. There should be no problem with starting the number 2 first even off the main battery, if you can't you probably need a new main batt or it needs to be deep cycled. The only time you are going to have problems is if you are starting all the time on external power (bad practice) as this will rape the batteries if you don't use them to start. We found this out a year or two ago. To be honest though there is not going to be much of a difference in time between starting with the batt or the EPU.

As for the quick start (which was developed for the EMS industry, I remember something about 3 mins for some reason, something to do with EMS operators in Europe. However, it was quite a while ago I heard this so I may be mistaken)...I have never tried it but if you like I can certainly try it tomorrow and come up with a time for you from seltbelts on to take off. I would estimate around 3-4 minutes if all the system checks have been completed.

Have any of the 139 operators considered replacing the Ni-cad batteries with CONCORDE sealed lead acid batteries ?

They ( CONCORDE ) have numerous STC's for 'other' type / models helicopters but haven't seen one for the 139. Perhaps the right time to put pressure on AW to evaluate and approve

One of the advantages -of sealed lead acids- over Ni-cads is that one will not have any more problems with -defective- battery temp warning systems that warns you for a thermal runaway .

A phenonemon invented by MARATHON, probably triggered by the MARATHON 'bossom buddies' that used to 'parade' around the annual HAI shows in the eighties....

Aser,

Just noticed that deviation to the right recently and checked it again last night, same thing. Deviation indicator in the middle of the course needle also flickering left and right off centre by a couple of mm from about 6miles out. As you say, fully coupled and using IAS mode to back off the speed as we came in. We'll run some checks next week but when it auto levels, I like to see it run down the centreline - much warmer feeling!!

Yes, I've tried the DCL mode but rather than claim it doesn't work, I'm going to double-check what the RFM says about using it. I thought I was doing it right but.....................

As for the battery start for number two, I agree it shouldn't be a problem and I'd have done it more often if I'd known about the PW 10% requirement, so I'm just going to start #2 first whenever I can now. I'd prefer to see closer to 24v than 23v (just me being cautious)for #2 so I've even started to carry a hand held - the last thing I want to hear is "Standby" after calling Ground for start at some major airport or other (hate bloody airports, I do).

Is it just me, or do you get accustomed to the higher vibe, or does it settle down after a bit? I feel it increasing through about 142/143 knots (pretty common) but the last couple of trips, I've pegged it at the highest speed IAS mode will allow (e.g., 153KIAS at 4,500 ft) and just left it there, before long I'm wondering where the vibe has gone?

Aser

Did the DCL thing a couple of times today. It did the decel to 80kts fine but the same as you each time, off to the right but came back in to the centreline over the numbers. I let it continue to ALVL, otherwise it would have been aligned with the grass to the right side at DH.

PM me with some contact details, please.

22

AW 139 Cat A Ops
 

"1. The optimum Nr for rotor performance is 100% (any more or less and the rotor is LESS efficient)

2. In order to meet the RFM Cat A performance standards, any OEI flight during take off and landing must be conducted with the remaining engine at maximum power.

3. To ensure that this is so, the collective lever must be raised until the Nr droops. This will bring the remaining engine up to maximum power. If the remaining engine is NOT at maximum power then the performance promised in the RFM cannot be guaranteed.

4. If the starting point was 100% Nr then this would mean that when the Nr was 'drooped' to say 98% then the rotor was working at a less efficient speed so the Nr is set to 102%. Thus, when the Nr is drooped it will droop to 100% where it should remain until Vtoss is achieved.


Comment!

1. Type specific ;)
2&3. Obvious, and applicable to any type :ok:
4. Gobbledygook :confused:

212man
 

It's 'Guess The Question' time. The question you answered is not the question being asked - apologies for sounding a bit like Donald Rumsfeld.

The statement posted was in response to the much asked question

"Why do we select 102% Nr for Cat A ops but not for Cat B Ops - or for that matter during OEI ops"

The only answer I can find that fits the published info is the one given. Apologies if you find it gobbledegook. If you tell me which bit you don't understand the I will try to explain further. Other 139 guys seem to get it but maybe you are not familiar with the type.

G

AW 139 Cat A Ops
 

It depends what is your flight condition or flight profile. For Cat A operations optimum NR is 102% as pubblished
In order to meet the RFM Cat A performance you have to stick to RFM procedures that are quite clear. FADEC will take care of the power once you take care of the pubblished procedures
Not true, collective has to be kept at the same position of a standard AEO maneuvre unless a droop is necessary to achieve transational lift to accelerate to Vtoss
The starting point for Cat A can only be 102%. The droop is allowed up to 90% and is not meant to achieve a better efficiency but to convert the huge M/R inertia into transational lift, once you have achieved Vtoss you have to recover your 102% NR setting.

100% Nr is only for Cat B because there is no need for extra power to ensure best Cat B performance in the entire envelope.

Bpaggi
 

It depends what is your flight condition or flight profile. For Cat A operations optimum NR is 102% as pubblished

With respect the aircraft does not know whether you are flying Cat A or Cat B so the type of profile selected cannot affect the rotor efficiency. It is either more efficient at 102% or not. If it is more efficient then why not use it for Cat B ops and for OEI landings? I suspect, but I don't know (and I wish I did) that the helicopter is designed to fly at 100% because that is the most efficient Nr.


In order to meet the RFM Cat A performance you have to stick to RFM procedures that are quite clear. FADEC will take care of the power once you take care of the pubblished procedures

The FADEC (actually it's not a FADEC but I know what you mean) will only deliver if you put the collective in the right place. As the RFM invites you to adjust collective during the response to engine failure it may not be in the right place to get max power from the remaining engine. 'FADEC' wont help you then.


Not true, collective has to be kept at the same position of a standard AEO maneuvre unless a droop is necessary to achieve transational lift to accelerate to Vtoss

Well the only practical way I know that you can be sure the remaining engine is at max power is to pull until the NR droops. Exactly how much droop would depend on the circumstances.


The starting point for Cat A can only be 102%. The droop is allowed up to 90% and is not meant to achieve a better efficiency but to convert the huge M/R inertia into transational lift, once you have achieved Vtoss you have to recover your 102% NR setting.

Agree

100% Nr is only for Cat B because there is no need for extra power to ensure best Cat B performance in the entire envelope.

Surely any wise pilot who believes that 102% Nr endows the machine, in some way, with better performance, would select 102 for every take off - A or B.

I am not sitting here thinking I know all the answers that's why I'm enlisting Ppruners help and advice but if it's not published by AW then I have to be sceptical. If AW say 102 is good for Cat A but not for Cat B then I have to look deeper for an answer. It cannot be performance, it must be technique. Somebody show me otherwise and I'll be a happy man.

G

:} :{

Humm...
" SINGLE ENGINE FAILURE, RECOGNIZED AT/AFTER TDP (CONTINUED TAKE OFF)"
1. [...].Mantain 0º while using collective to droop NR to minimum of 90% and set 2.5min. power.

Yes, "quite clear" :E

Anyway... if you are taking off at any Tq. above 80% I don't think you need to use collective, the "droop" will be automatic. If you are very light you may need to use collective to drop NR and use all the power the engine can give (if you need it).

Geoffersincornwall, how is it in the sim at MGW ? I'd like to go there some day.


EDIT: I think the rotor is more efficient at NR 90% than 100% at 2.5min power , in the transition to Vtoss. No?

Regards
Aser

A stimulating experience
 

The sim as a fantastic tool but as with any such device will only deliver according to the software. It is supposed to be accurate but how do you know when the only real aircraft training is done using the OEI training switch - which is a great tool in itself.

I'm currently doing a customer's TR course and due to their location have cranked up the OAT to 35 - 40 degrees. At that temp and with no wind the machine does the job with no fuss. A higher MTOM will be interesting but we are waiting to hear officially about that.

Enjoying the job very much but wish that the flow of information was a little better. Physically I am near the centre of the AW world but info-wise I could be the other side of the world. That's the trouble when you are not important enough.

Hope to see you one day.

G

Geoff, you are right - I am not familiar with the type and maybe the quote would appear more logical in a wider context.

What I would say is this: For a CAt B procedure, the only pre-requisite is the ability to hover IGE AEO. Nothing is guaranteed in the way of OEI performance either for a rejected take off or continued (or attempted continued!) Take off. Therefore, it would make sense to operate the aircraft at the most efficient Nr when AEO, which seems to be 100%, as this is the only flight regime being recognised by the RFM.

For a CAt A procedure, everything is predicated on the subsequent OEI performance, so it would make sense to operate such that in the event of an engine failure, the aircraft then enters the optimum OEI conditions. It would seem that the natual Nr decay for this type (as quoted) is about 2%, therefore setting 102% for AEO ops would place the aircraft at 100% in the transition to OEI.

Of course, at the end of the day it all depends what you do with the lever after the failure and I'm assuming the quoted decay is the normal result of leaving the collective position alone.

I hope this ties in with your dilema?

http://cdn-www.!!!!!!!!!!!!!!/photos.../8/1337886.jpg
http://www.!!!!!!!!!!!!!!/photo/UK---...39)/1337886/L/

Nice nose... :ok:

Geoffersincornwall
 

Of course the aircraft does not realize whether it's flying at 100 or 102%. For AW139 Cat A operations 102% has not been selected to have the best rotor efficiency but to achieve the best Cat A performance. So in this terms the best aircraft efficiency is 102% NR

Actually is FADEC and nothuing else that it'll take care of the power delivered topping the engine at 2.5' rating and giving you always the max power available. Collective has to be kept at the same position most of the times and when needed (at the extreme of the nevelope) pulled in order to droop the rotor as much as required to achieve transitional lift.

You do not need to know whether the engine is at max power, you need to carry out the reccomended procedure. Actually you need to watch NR gauge and not PI. Many conditions will not require max OEI power to carry out the procedure.

If you operate the aircraft within the RFM limitations you'll have huge safety margins at 100% NR in the whole Cat B envelope respecting the certification requirements.

212man

The reason 102% has been selected is not to achieve 100% when the rotor droops but to have a greater inertia reserve down to 90% when is required

Geoff,

Firstly, bpaggi (if he is who we think he is) should know, and I would bow to his superior knowledge; it is nice having someone who is at the sharp end of Flight Testing prepared to confirm/refute such statements. Like 212man - I would like to qualify my statements, as he does, by stating that I have no intimate knowledge of the AW139 performance.

Category B performance consists of the provision of AEO data - one of which elements is the provision of "the horizontal distance required to take-off and climb over a 15 m (50-foot) obstacle"; one of the conditions of that manoeuvre is that "a landing can be made safely at any point along the flight path if an engine fails" - which we can assume to mean that the trajectory remains outside the HV diagram. As this is conducted at AEO, we can assume that the most efficient condition of rotor-speed is used (in your text 100%) - no failure is assumed.

Category A - for all of the noise we make about it - is mostly about distances. Under normal circumstances, we can assume that distances are critical only if the engine fails at the critical point - which is at TDP (minus the pilot recognition and intervention time - i.e. one second unless otherwise justified and accepted). The distances are: the rejected distance; and the take-off distance. These distances are specified with one-engine-inoperative.

In meeting the requirement for the rejected distance, the point in space at which the engine-failure is assumed to occur plays its part. TDP is the last point at which the pilot has to be able reject the take off and land; field-of-view and the (average pilot's) ability to fly the helicopter into the area provided by the rejected take-off distance available dictates where this point can be in a vertical and horizontal sense.

For the take-off distance; the pilot must, with a failure recognised at the critical point, be able conduct a contined take-off and avoid all obstacles in achieving the the projected take-off distance required at the appropriate conditions. The achievement of this distance also depends on the point in space of the TDP.

However, as procedures have become more sophisticated, the total energy package has had to be considered; in that package are a number of potential benefits (mainly for the continued take-off - for the rejected take-off, some of these could, if exceeded, be disbenefits): the vertical acceleration at the point of failure; the potential energy contained at the height of the TDP; and the energy stored in the rotor before it is drooped (to the manufacturers recommended setting).

As you well know, this total energy package is used extremely effectively in achieving the OEI trajectory to avoid the take-off surface; in an elevated procedure, it provides the deck-edge miss and utilises the drop down to recover the rotor speed (to 100%?) and provide acceleration to Vtoss.

Now to return to the initial point; the conditions for the Cat A procedure are optimised to utilise all engergy at a single critical point of failure. If that point is passed with all-engines-operating, the procedure ceases to be critical unless (and I can't imagine why this would be the case), the single engine profile is flown with AEO.

Jim

MMMMMMMMMMMmmmmmmmmm........
 

Lots to think about there.

Bpaggi - just to clarify I said that the aircraft doesn't know if it's being operated Cat A or Cat B not that it was unaware of the NR ...... it obviously IS.

My situation is that I have to teach exactly what it says in the RFM/QRH and my colleagues and I try hard to do that. We are however beginning to encounter other (very professional) colleagues from around the world who come for their recurrent training and bring with them their intelligent interpretations of the gaps and ambiguities of the master documents such as the RFM.

What we crave is the aviation equivalent of that wonderfully interesting DVD that often accompanies the Movie DVD - "How it was made" "Interviews with the director".....That kind of background stuff would enable those of us in the firing line to deliver not only 'technique' but also 'understanding'


It is desperately frustrating to have the opportunity to deliver an accurate and meaningful contribution to the safe and effective operation of this great helicopter only to be starved of background info. We have tried asking more experienced AW colleagues but cannot get a consistent answer. Whatever we get we need it from those that know and in writing.... please.

If Bpaggi can help further would love to chat.

G

:ok:

PS - Doesn't a proper FADEC include control of the starting cycle???

Geoff, you're perfectly right. You all operators need to know how and why everything was made. We are perfectly aware of that and we have already (as a company) organized a meeting with the Italian Corporates Pilots where we gave a presentation on how we built the AW139 Take Off and Landing procedures.

I also think we need all possible feedbacks from you because everything is made for you.

I'll start working on this and I'll let you know as soon as possible what we can organize.

I'm also available in this forum whenever I can.

Yes FADEC includes also control starting cycle.

To answer ASER's statement;
"I think the rotor is more efficient at NR 90% than 100% at 2.5min power , in the transition to Vtoss. No?"

Next time you have an aircraft for training, sit in a high hover in a high power situation, out of wind, and get the training captain to fail an engine. If you droop the NR down toward 90% you will find the Aircraft will sink. By lowering the collective and allowing the NR to increase toward 100% the aircraft will start to climb, indicating the increase in efficiency of the rotor system at 100%NR. :ok:

Thanks pitchlink,
It was really a question.
I was just thinking about the possibility that at 90% we were using more pitch, more thrust from rotor, and all the possible power from the engine,even at less rotor speed.

Now, re-reading the posts from Geof,bpaggi and you. I understand the NR droop is just a "tool" to jump into flight,
Regards
Aser

bpaggi

The gathering of Italian Corporate Pilots was a great idea, especially with regard to the operation of the 139. However, it seems a pity it was confined to corporate pilots (after all, the aircraft neither knows nor cares who or what is in the cabin) and only to Italian pilots.

Unless, of course, there is a plan to disseminate any useful infromation from that meeting to other interested parties, or, even better, to repeat the exercise in the different theatres where the aircraft is operated.

Regardless of geographical location or type of operation, it's really silly that those of us who are lucky enough to fly but who also carry the accompanying responsibilities involved in operating this fine aircraft are still scrabbling around amongst ourselves to keep abreast of developments and in the search for explanations for different things, whether by e-mail, telephone or even here on PPRuNe.

And, while I'm at it, where the hell are we with the MTOW increase?

22

S.A.R. AW-139 Promo Video from Agusta Westland
http://youtube.com/watch?v=EJV4F_bRHVE

Best regards
Aser

Japan Coast Guard Takes Delivery Of Its First Three AW139 Helicopters
http://www.verticalmag.com/control/n...es/?a=7220&z=6
http://www.verticalmag.com/control/n...les/7220-1.jpg

No nightsun,no liferafts, and only one hoist but int the twin-hoist arm, strange.. :ooh:

Regards
Aser

Of course, the life rafts and Nitesun can be fitted later. Knowing Agusta, and their suppliers, stocks are running low! ;)

Now that we had the chat about the CAT A 102% thing...

1-Can we also say that the reason we must(by flight manual) use 102% for Hoist & External loads ops. is related to OEI scenario and not rotor lift in hover?

2- Why don't we have an airspeed limit to arm floats in the supplement, is it tested up to VNE??

3- If you know that while in hover you are going down if engine quits, will you popout the floats before water contact? f.m. suggests to wait the water..

4- We are happy in floating in the water(after a really good ditching), we can not leave the rotor brake in "park" position due to the weight on wheels(I'm not talking about using rotor brake to stop rotors), isn't it?

Best regards & excuse the writing ;)

Aser
 

I am in pursuit of the many questions floating around at the moment and the latest contributions to the debate are:-

1-Can we also say that the reason we must(by flight manual) use 102% for Hoist & External loads ops. is related to OEI scenario and not rotor lift in hover?

The latest version of the answer to the '102%' query is that it appears that the helicopter was first certified under the 'Normal' Category and the 100% Nr became an RFM-set-in-stone feature. When the Cat A programme was under way the use of 102% was found to improve performance due to added rotor inertia. The 102% feature was then added via Supp 12. Draw your own conclusions but remember if you ding-it whilst working outside the RFM then the legal-beagles will come looking for your a**e. I remain in the hunt for the horses mouth.

2- Why don't we have an airspeed limit to arm floats in the supplement, is it tested up to VNE??

I'll chase that one

3- If you know that while in hover you are going down if engine quits, will you popout the floats before water contact? f.m. suggests to wait the water..

I guess we will have to wait for the first ditching to get some answers

4- We are happy in floating in the water(after a really good ditching), we can not leave the rotor brake in "park" position due to the weight on wheels(I'm not talking about using rotor brake to stop rotors), isn't it?
Mmmmmmmm we have said the same thing - must go find another horse!!

G

:ok:

Heliportugal
 

http://www.verticalmag.com/control/n...les/7350-1.jpg

Mmmmmmmm .........

I am just about to join the ranks of "Rated Pilot" on this wonderful machine .....

The "Mental Abuse" stage (Ground School) completed this last week ...... physical abuse to start next week (I bloody hope!).

;););)

Nothing quite like either an Italian Sports Car (?) OR a young Italian woman to take a bloke back to "before he had grey hair" stage of his life eh?

:E: :ok:

Remember German Car, Italy woman but never the other way around...

Ooooohhher .........

I've gotten that wrong already ....... girfriend is from Koln ..... but she is younger!


Quote from Groucho ....... "Your only as old as the woman you feel" :E

AW139 and using the FLOATS correctly
 

How many offshore guys have adjusted to using the floats correctly and armed them as you go outbound across the coast and vice versa when you make land? Do you disarm them whan on deck?

G
:ok:

Hi Geoff,
We disarm the floats after reaching Vy during after T.O checks, and arm them again at 90kts decellerating to the deck. I think due to the fact we had 2 inadvertent float deployments (on the ground) when we first got the aircraft! I'm sure you already know about that.
Maybe see you in August when I am due to be out in the sim.
Rgds

AW139 and using the FLOATS correctly "G"

Geoff, everyone is using them incorrectly. The AW139 has the safest, most practical float installation I've seen, yet everyone is stuck in historical practises of arming and disarming them constantly going through Vy. Do what you can when you are training pilots, maybe in a few years the lightbulb will come on.

I think other manufacturers should take a page out of Agusta's book and modify their float systems to do the same.

Pitchlink thinks it's OK to discredit a technical advance because some dufus can't follow a procedure. Time to move on everyone.