EC135
Joined: Nov 2010
Posts: 2
Likes: 0
From: us
EC-135 Aero Questions
I know the EC-135 has a hingeless rotor head where there is no mechanical hinge to speak of. However, there is a area or spot somewhere along the span of the EC-135 main rotor blade where the flapping motion occurs. It could be called the flapping point.
On the Dauphin's hingleless rotor head the main rotor hinge offset value is 6%.
On Bell two bladed main rotor head the main rotor hinge offset value is 0%.
The larger the main rotor hinge offset value the move maneuverable the
helicopter.
The Dauphin's normal hover attitude is 4 degrees pitch up and 3 degrees right wing down. This hover attitude does not change unless the helicopter is load outside its CG limits.
With the helicopter load within its CG limits, I just want to know what the EC-135 normal hover attiude is.
Thanks
On the Dauphin's hingleless rotor head the main rotor hinge offset value is 6%.
On Bell two bladed main rotor head the main rotor hinge offset value is 0%.
The larger the main rotor hinge offset value the move maneuverable the
helicopter.
The Dauphin's normal hover attitude is 4 degrees pitch up and 3 degrees right wing down. This hover attitude does not change unless the helicopter is load outside its CG limits.
With the helicopter load within its CG limits, I just want to know what the EC-135 normal hover attiude is.
Thanks
Joined: Oct 2007
Posts: 85
Likes: 0
From: europe
What do you use as your standard hover height when taxying etc, i have heard various figures (skid to ground)? 2feet? 3 feet? 4 feet? 7 feet? etc etc
One train of thought is to keep it close to the ground (2-3ft) so that in the event of an engine failure or TR drive failure you have got less of a drop, the downside of this is that if the aircraft is mishandled you increase the chance of a tail-strike or skid strike?
Any opinions??
One train of thought is to keep it close to the ground (2-3ft) so that in the event of an engine failure or TR drive failure you have got less of a drop, the downside of this is that if the aircraft is mishandled you increase the chance of a tail-strike or skid strike?
Any opinions??
Joined: Oct 2009
Posts: 105
Likes: 0
From: St Gallen
Floats for EC135
Hi
In summer I plan to fly with EC135 to Norway. Since the trip requires some small sea crossing and there is a lot of Fjords in Norway, my question is about floats. I am pretty sure, that any chopper goes under water like rock, and spinning rotor can kill anyone who tries to escape.
During my type rating, my instructor enjoyed shutting down one engine almost constatnlly, so I know thay EC135 is able to reach shore with OEI under any situation. Do I really need the floats for my trip or not? which other survivable emergencies I can have, where floats can help?
In summer I plan to fly with EC135 to Norway. Since the trip requires some small sea crossing and there is a lot of Fjords in Norway, my question is about floats. I am pretty sure, that any chopper goes under water like rock, and spinning rotor can kill anyone who tries to escape.
During my type rating, my instructor enjoyed shutting down one engine almost constatnlly, so I know thay EC135 is able to reach shore with OEI under any situation. Do I really need the floats for my trip or not? which other survivable emergencies I can have, where floats can help?
Joined: Aug 2007
Posts: 30
Likes: 0
From: UK, sometimes
Besides a double engine or tail rotor failure, you need to look at how short your sea crossings are. Don't forget that a minor issue over land of Fuel Transfer Pump failures can make you sweat over the sea if more than ~20mins from land (if fuel in the main tank isn't high enough to slosh over in the supply part).
At least with floats it does give you an option, albeit not the best one.
But, if it is a private flight, the choice is yours.
At least with floats it does give you an option, albeit not the best one.
But, if it is a private flight, the choice is yours.
Joined: Sep 2000
Posts: 1,605
Likes: 6
From: UK
Fuel transfer pump failure worst case scenario would be you can't get the last 60kg if you go faster than 80kts with the forward pump failed but if you slow down to below 80kts then it's only 4kg. If the rearward one fails and you go faster than 80kts minimum unusable fuel will be 7.5kg.
I hope that helps.
If it was me flying private and I know the machine I would be happy to go without floats.
I personally think woodland would be more dangerous compared to water, and they don't do floats for woods.
I hope that helps.
If it was me flying private and I know the machine I would be happy to go without floats.
I personally think woodland would be more dangerous compared to water, and they don't do floats for woods.
Joined: Oct 2009
Posts: 105
Likes: 0
From: St Gallen
Problems with main tank in EC135
Hi
Several months ago I have started to have problems with fuel QTY meter in main on my 2008 EC135P2+. The symptoms was FULE QTY DEGR message, and faulty indication in main tank. Talked to maintanence, they suggested water in fuel so I have drained tank, refueled and added a little bit of Priest in order to get rid of water. When ever I put some priest I went to fly to consume the prist with fuel. It helped.
When the chopper went to 100hrs inspection I suggested to check fuel QTY meters in main tank, and WHAT A SH.....T!!!!!!
The main tank in the rear area is completelly unbonded and separated. Sending photo. Eurocopter suggest to get new main tank, and since chopper is still under warranty, my main concern is what is the cause of the problem and who will pay for it.
Have you ever seen something like this. The helicopter was a long time in Malaysia on the ground, waiting for customer. Do you thing that some kind of bacteria can cause this? Do you thing Priest can destroy the tank in such a way? Except for Priest I am not aware of any other additives in fuel. And I have personally refuelled only in HEMS heliports, and good airports in Czech Republic a Switzerland, where good quality of fuel can be expected.
Several months ago I have started to have problems with fuel QTY meter in main on my 2008 EC135P2+. The symptoms was FULE QTY DEGR message, and faulty indication in main tank. Talked to maintanence, they suggested water in fuel so I have drained tank, refueled and added a little bit of Priest in order to get rid of water. When ever I put some priest I went to fly to consume the prist with fuel. It helped.
When the chopper went to 100hrs inspection I suggested to check fuel QTY meters in main tank, and WHAT A SH.....T!!!!!!
The main tank in the rear area is completelly unbonded and separated. Sending photo. Eurocopter suggest to get new main tank, and since chopper is still under warranty, my main concern is what is the cause of the problem and who will pay for it.
Have you ever seen something like this. The helicopter was a long time in Malaysia on the ground, waiting for customer. Do you thing that some kind of bacteria can cause this? Do you thing Priest can destroy the tank in such a way? Except for Priest I am not aware of any other additives in fuel. And I have personally refuelled only in HEMS heliports, and good airports in Czech Republic a Switzerland, where good quality of fuel can be expected.
Joined: Jun 2004
Posts: 33
Likes: 0
From: Canada
ILblog,
I have seen Prist eat fuel tanks before if the concentration was too high. On
different aircraft types with bladder style tanks.
(I mean way too high. I can't bring to mind the proper ratio but I want to say
something very low like .16% is good and the one case was caused by a bad
injector on a fuel truck which left globs of Prist in the tank.)
As a side note, are you not draining your sumps before the first flight of the day in order to eliminate any water from condensation etc?
I would like to put that question to the general populace on here as well. Over
the years, the number of people I have met who cannot be bothered boggles
the mind.(That does not include operations in sub-zero temperatures for those who were going to bring it up.)
Rigidhead
I have seen Prist eat fuel tanks before if the concentration was too high. On
different aircraft types with bladder style tanks.
(I mean way too high. I can't bring to mind the proper ratio but I want to say
something very low like .16% is good and the one case was caused by a bad
injector on a fuel truck which left globs of Prist in the tank.)
As a side note, are you not draining your sumps before the first flight of the day in order to eliminate any water from condensation etc?
I would like to put that question to the general populace on here as well. Over
the years, the number of people I have met who cannot be bothered boggles
the mind.(That does not include operations in sub-zero temperatures for those who were going to bring it up.)
Rigidhead
Joined: Jul 2008
Posts: 372
Likes: 0
From: Australia
Weak fillet bond failure
IL Blog
From the photograph, there appears to be weak fillet bond failure where the core disbonds from the adhesive fillets. The adhesive fillets are formed during the initial bonding process, and they are essential for the strength of the bond. There is a conference paper on this:
Davis, M.J., Chester, R.J., Perl, D.R., Pomerleau, E., Vallerand, M., Honeycomb Bond and Core Durability Issues; Experiences within CREDP Nations, Aging Aircraft Conference, Williamsberg, VA, Aug 31-Sep 02 1998.
If you google that, there is a copy on my web site.
Essentially, the core simply separates from the adhesive layer leaving very little damage to the core or the adhesive layer. Typically once the core to adhesive bond is degraded, the flat-wise tensile strength (the strength of the core out-of-plane) falls to about 10% of original manufacture. This has been the cause of a significant number of rudder faiiures on one type of military aircraft. It is caused by water entering into the honeycomb panel itself, not just into the fuel tank, but actually penetrating the space between the inner and outer skins of the panel. This can only occur if there is a defect (such as a disbond of an edge member or a panel penetration which may have been repaired) which must occur first to enable the water to enter the core.
This type of failure should not occur if the water can be kept out of the core, so it is important to find where the water is getting in, not just to repair the part.
Regards
Blakmax
From the photograph, there appears to be weak fillet bond failure where the core disbonds from the adhesive fillets. The adhesive fillets are formed during the initial bonding process, and they are essential for the strength of the bond. There is a conference paper on this:
Davis, M.J., Chester, R.J., Perl, D.R., Pomerleau, E., Vallerand, M., Honeycomb Bond and Core Durability Issues; Experiences within CREDP Nations, Aging Aircraft Conference, Williamsberg, VA, Aug 31-Sep 02 1998.
If you google that, there is a copy on my web site.
Essentially, the core simply separates from the adhesive layer leaving very little damage to the core or the adhesive layer. Typically once the core to adhesive bond is degraded, the flat-wise tensile strength (the strength of the core out-of-plane) falls to about 10% of original manufacture. This has been the cause of a significant number of rudder faiiures on one type of military aircraft. It is caused by water entering into the honeycomb panel itself, not just into the fuel tank, but actually penetrating the space between the inner and outer skins of the panel. This can only occur if there is a defect (such as a disbond of an edge member or a panel penetration which may have been repaired) which must occur first to enable the water to enter the core.
This type of failure should not occur if the water can be kept out of the core, so it is important to find where the water is getting in, not just to repair the part.
Regards
Blakmax
Joined: Sep 2000
Posts: 1,605
Likes: 6
From: UK
VEMD Dimming
When you select Instrument lighting the VEMD dimms a bit but not great lot which means you manually have to dimm it further.
How come when you enter the Maintenance pages it dimms out right proper?
How come when you enter the Maintenance pages it dimms out right proper?
Joined: Nov 2006
Posts: 1,951
Likes: 90
From: After all, what’s more important than proving to someone on the internet that they’re wrong? - Manson
Brilliant Stuff,
I wouldn't hold your breath on that one.
How come when you want scroll through the flight reports and other data pages you press - to advance the number and + to go back?
Transverse lobotomy = FR?
Try turning both VEMD lanes off and watch the resultant analog data in the CAD. Ng or TOT whether TM or PW. Sometimes does some weird things!
I wouldn't hold your breath on that one.
How come when you want scroll through the flight reports and other data pages you press - to advance the number and + to go back?
Transverse lobotomy = FR?
Try turning both VEMD lanes off and watch the resultant analog data in the CAD. Ng or TOT whether TM or PW. Sometimes does some weird things!
Joined: Aug 2000
Posts: 3,670
Likes: 1
From: UK
It's not just that (mechanical - fire/hydraulic/mgb etc) if I were you, I would check with my insurance company also! If you do stoof overwater without floats (even though you don't legally need them) the insurance company might seriously reduce the pay out because you haven't taken appropriate steps to protect the aircraft.
Joined: Jun 2004
Posts: 646
Likes: 18
From: Europe
I'm refreshing EC knowledge and I can't find an answer to my question:
Herr Balick (the one just under the god of EC135)
was my instructor for ground school and I made a note on Mast Moment Indication System:
"Caution range 50-66% yellow - NO TIME LIMIT"
Why did I wrote that as we can clearly find the accumulated time for both yellow and red MM range on VEMD?
I checked what I could find in the maintenance manual - found nothing except how to take it apart - so, does yellow "caution" range represent maintenance action after certain accumulated time or not?
Nothing in the FLM supplement also... except for the red markings - entry in logbook + maintenance action.
Herr Balick (the one just under the god of EC135)
was my instructor for ground school and I made a note on Mast Moment Indication System: "Caution range 50-66% yellow - NO TIME LIMIT"
Why did I wrote that as we can clearly find the accumulated time for both yellow and red MM range on VEMD?
I checked what I could find in the maintenance manual - found nothing except how to take it apart - so, does yellow "caution" range represent maintenance action after certain accumulated time or not?
Nothing in the FLM supplement also... except for the red markings - entry in logbook + maintenance action.