rolling take-off
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Careful though...
Helicopter wheel braking systems are usually designed to prevent the aircraft from moving - not to slow the aircraft or to assist in a taxi turn.
Helicopter braking systems on some (older) types are more prone to overheating, and an overheating brake disc will expand and may seize the wheel concerned.
Airplane brakes ARE designed to slow a fast moving aircraft and therefore have better heat resistant properties.
If the procedure's not in the flight manual.....
Helicopter braking systems on some (older) types are more prone to overheating, and an overheating brake disc will expand and may seize the wheel concerned.
Airplane brakes ARE designed to slow a fast moving aircraft and therefore have better heat resistant properties.
If the procedure's not in the flight manual.....
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Running take offs are still often used by RN Sea Kings in an attempt to prolong the life of those venerable old airframes. It's also an SOP when embarked in an aircraft carrier and the ship can't manoeuvre to generate sufficient relative wind to keep the aircraft within the Ship's Helicopter Operating Limits. It's easier to conduct an aft facing running take off (relative wind permitting), forward facing take offs require the pilot to dodge around the ship's ski jump ramp.
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I use rolling take-offs and rolling landings everyday when operating from airports (runways and taxiways).
The simple reason is, for a twin engine wheel equipped aircraft with marginal single engine performance, it is the safest take-off and landing profile in the event of an engine failure. They are not difficult. Every pilot of a wheel equipped twin should be proficient at doing them.
I don't use them to get a heavy machine into the air. That's why we do a weight and balance.
The simple reason is, for a twin engine wheel equipped aircraft with marginal single engine performance, it is the safest take-off and landing profile in the event of an engine failure. They are not difficult. Every pilot of a wheel equipped twin should be proficient at doing them.
I don't use them to get a heavy machine into the air. That's why we do a weight and balance.
It's not just an adventure....
it's just a job!
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Hi All,
I used to do rolling take-offs in the 76 from any runway, purely to expedite the take-off. However, since the latest data about the 76 gear and its recurring instances of gear collapse during taxi, I don't think I will be using this practice anymore. Just ask the Air Ambulance drivers in Ontario!
OffshoreIgor
I used to do rolling take-offs in the 76 from any runway, purely to expedite the take-off. However, since the latest data about the 76 gear and its recurring instances of gear collapse during taxi, I don't think I will be using this practice anymore. Just ask the Air Ambulance drivers in Ontario!
OffshoreIgor
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When spraying with B-47 G-1A and carrying 80 gallons in the heat of the day it's the only way into the air. 60 gallons works a lot better but still never come to a hover. Running takeoff iis so much easier on machine (even with skids).
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76 takeoffs
Sorry XNR! Gotta disagree!
The safest 76 takeoff is the Cat A within Cat A weights....performance is GUARANTEED. Especially if, as you say, coming off a runway.
The rolling t/o opens up a whole new world of hurt. Just ask some of the OKIE guys about cracked windshields, blown tyres, and such. Also, holding that nose 5degrees down so close to the ground after liftoff can lead to a "situation" when OEI.
The rolling t/o can be used as a risk management "profile" for FOD avoidance.
DK
The safest 76 takeoff is the Cat A within Cat A weights....performance is GUARANTEED. Especially if, as you say, coming off a runway.
The rolling t/o opens up a whole new world of hurt. Just ask some of the OKIE guys about cracked windshields, blown tyres, and such. Also, holding that nose 5degrees down so close to the ground after liftoff can lead to a "situation" when OEI.
The rolling t/o can be used as a risk management "profile" for FOD avoidance.
DK
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DK
Don't know why I would be 5 degrees nose down after a rolling takeoff. But you might be 5 degrees nose down as you begin your Cat A.
Of course you could blow a tire rejecting a Cat A as well.
Don't know why I would be 5 degrees nose down after a rolling takeoff. But you might be 5 degrees nose down as you begin your Cat A.
Of course you could blow a tire rejecting a Cat A as well.
Last edited by Xnr; 4th Dec 2005 at 01:47.
Avoid imitations
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A rolling takeoff is a way of getting the aircraft through translational lift while it's on the ground and a method of getting airborne using minimum power.
There is no requirement for it in performance Category A / Class 1. As I mentioned earlier, the RAF taught it for limited power situations, such as when overloaded or when single engine in a twin.
It's also a safe way of getting airborne in an environment where, if a hover is attempted, the pilot's view might be badly impaired by blowing dust / debris or snow, or a turbine engine might ingest same and be damaged. The advantage is that the aircraft leaves it's downwash behind it.
It's just another a tool in the pilot's toolbox of skills, it's not meant to be used routinely.
There is no requirement for it in performance Category A / Class 1. As I mentioned earlier, the RAF taught it for limited power situations, such as when overloaded or when single engine in a twin.
It's also a safe way of getting airborne in an environment where, if a hover is attempted, the pilot's view might be badly impaired by blowing dust / debris or snow, or a turbine engine might ingest same and be damaged. The advantage is that the aircraft leaves it's downwash behind it.
It's just another a tool in the pilot's toolbox of skills, it's not meant to be used routinely.
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XNR,
No danger at all. It is in your bag of tricks, and one of the reasons why wheels are desirable.
The landing gear is not harmed by normal taxi operations, the structural loads are peanuts, unless you are driving around through potholes.
I am surprised at those who think rolling takeoffs "save" the aircraft structure from stresses. The hover stresses are so low they usually cannot be measured, it is the high speed that eats at the aircraft - and I don't think you want to taxi at 150 knots!
No danger at all. It is in your bag of tricks, and one of the reasons why wheels are desirable.
The landing gear is not harmed by normal taxi operations, the structural loads are peanuts, unless you are driving around through potholes.
I am surprised at those who think rolling takeoffs "save" the aircraft structure from stresses. The hover stresses are so low they usually cannot be measured, it is the high speed that eats at the aircraft - and I don't think you want to taxi at 150 knots!
I think the key point is not whether the wheels etc are being stressed, it is to what regulations and in what context you are operating. If you are operating to public transport standards using a FLM Cat A procedure, you are effectively entering a grey area by carrying out a running take off, as you have just reinvented the wheel (no pun meant!) The FLM describes the profile used, associated with the take off and rejected take off distances obtained from the graphs, but you are not following it. If you are at the correct WAT weight you will also gain no weight advantage by choosing to do a running take off instead, either.
On the other hand, if you are operating to Cat B, do what you like! Similarly in the military.
On the other hand, if you are operating to Cat B, do what you like! Similarly in the military.
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The customer's view
Just a passing thought that we as pilots should bear in mind.
The debate has identified those situations where the rolling take-off can reduce the problems caused by FOD or snow/sand/dust. We have to concede that this is a judgement-call of the sort we get paid to make.
That said I cannot support the notion that routine running take-offs from runways on public transport flights is a 'good thing'. It's not!
The customer's view is that he wants the helicopter to be operated at minimum risk to his employees (the passengers). This means that you WILL establish HIGE and you will thereby determine that your expectations with regard to the mass of the load carried and the power (Tq) used in the HIGE are realistic and as you expect.
There was a recent case of a 332 being found to be 600lb over the MCTOW after the crew questioned the manifested load from the platform and had it checked after their safe arrival at base.
Mistakes do happen!
I've always thought that what marked chopper drivers out from their ignorant fixed wing cousins is that we have a lot more sense than to sit at the end of a piece of concrete, wind the engines to full chat, let the brakes off and then hope that you will get airborne before the concrete runs out.
Much better that you get airborne first, check all is well, then blast off into the blue.
G
The debate has identified those situations where the rolling take-off can reduce the problems caused by FOD or snow/sand/dust. We have to concede that this is a judgement-call of the sort we get paid to make.
That said I cannot support the notion that routine running take-offs from runways on public transport flights is a 'good thing'. It's not!
The customer's view is that he wants the helicopter to be operated at minimum risk to his employees (the passengers). This means that you WILL establish HIGE and you will thereby determine that your expectations with regard to the mass of the load carried and the power (Tq) used in the HIGE are realistic and as you expect.
There was a recent case of a 332 being found to be 600lb over the MCTOW after the crew questioned the manifested load from the platform and had it checked after their safe arrival at base.
Mistakes do happen!
I've always thought that what marked chopper drivers out from their ignorant fixed wing cousins is that we have a lot more sense than to sit at the end of a piece of concrete, wind the engines to full chat, let the brakes off and then hope that you will get airborne before the concrete runs out.
Much better that you get airborne first, check all is well, then blast off into the blue.
G
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Not flying Cat A.....standard configuration......W&B within limits.....do it myself....but the main reason I like to roll on and off is the we have had 2 engines cough their 3rd stage turbine wheels this year.... so if I am already set up to roll it on I really dont care if 1 quits.........well of course I care but it shouldn't hurt me, the other engine or the aircraft.
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I hope that as running take-offs are routine in my helicopter operations I am not marked down as ignorant in the eyes of the wider rotary community Geoffersincornwall?
Regards
HEDP
Regards
HEDP
Avoid imitations
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"Shy
The danger in using them routinely is ........?"
Xnr, I didn't mention danger....why danger?
As Nick said, there isn't one. It might just not be appropriate. If you are operating to Performance A / Class 1 it isn't normally called for. However, to give an example, if I was operating from a runway with blowing snow, I might elect to use the technique to reduce the chance of disorientation from seeing recirculating snow in the beam of the searchlight.
The danger in using them routinely is ........?"
Xnr, I didn't mention danger....why danger?
As Nick said, there isn't one. It might just not be appropriate. If you are operating to Performance A / Class 1 it isn't normally called for. However, to give an example, if I was operating from a runway with blowing snow, I might elect to use the technique to reduce the chance of disorientation from seeing recirculating snow in the beam of the searchlight.
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There is a time and a place for everything. Running take-offs and landings with skid equipped helicopters and rolling take-offs and landings with wheeled equipped helicopters are nothing more than another tool in the professional helicopter pilot's tool box.
We practice them in the Apache on nearly every training flight even though rolling take-offs are only used with external tanks and rolling landings would only be used in the even of single engine failure or some other emergency landings. The same is true of all wheeled aircraft.
I have rarely used running take-offs with skid equipped helicopters but have frequently used running landings for both normal and emergency landings.
Helicopter pilots should be able to perform running landings, rolling landings, landings to an IGE hover, landings to an OGE hover and landings to the ground. Each will be used during a helicopter pilots career one time or another depending on the circumstances he/she confronts.
We practice them in the Apache on nearly every training flight even though rolling take-offs are only used with external tanks and rolling landings would only be used in the even of single engine failure or some other emergency landings. The same is true of all wheeled aircraft.
I have rarely used running take-offs with skid equipped helicopters but have frequently used running landings for both normal and emergency landings.
Helicopter pilots should be able to perform running landings, rolling landings, landings to an IGE hover, landings to an OGE hover and landings to the ground. Each will be used during a helicopter pilots career one time or another depending on the circumstances he/she confronts.
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We used to have a single engined ferry alleviation in the Bristow Ops Manual for the Bell 212.
VMC Day Only - 2500ft agl transit for Auto, non hostile terrain.
We therefore practised these at Base Checks - alright on grass but wore the skids out if on concrete/asphalt.
Used to always include the same technique when doing checks on AS355 pilots as I put the same alleviation in PDG's Ops Manual.
I think extended use of imbalanced power into C'Box may be an issue as this may not be covered in gearbox airworthiness certification.
UG
VMC Day Only - 2500ft agl transit for Auto, non hostile terrain.
We therefore practised these at Base Checks - alright on grass but wore the skids out if on concrete/asphalt.
Used to always include the same technique when doing checks on AS355 pilots as I put the same alleviation in PDG's Ops Manual.
I think extended use of imbalanced power into C'Box may be an issue as this may not be covered in gearbox airworthiness certification.
UG