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I've been flying helicopters for the past 10 years for the Marine Corps, and look forward to transitioning to HEMS after retirement. One curiosity I have though, every EMS helicopter take off I've seen in person or on video shows them climbing vertically to about 100'AGL before transitioning.

In the military, we teach to fly certain height/airspeed combinations to be right in the middle of the green portion of our Height/Velocity diagrams, should we lose an engine on transition. Obstacle take offs are obviously different because we want to get up and over them before transitioning, but EMS helos do these same vertical take offs regardless of what's in front of them or not.

Can anyone tell me why EMS pilots do vertical take offs from ~100'AGL before transitioning?

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The vertical in and out of scenes is designed to minimize exposure to obstructions, especially wires. Power failures are less likely than wires...

The approach terminates above immediate obstacles, followed by a slow vertical descent to the ground to allow you stop as quickly as possible if and when you suddenly see a new obstacle, or something happens in the scene.

The vertical climb out of the scene allows you to ascend through that same clear area you just landed through. Most EMS operations use aircraft with the power to do this predictably.

Pedal turns below the obstacles are discouraged, too.

 

Yeah, I thought it was goofy when I started this. There's a lot or wires (and other stuff) where we operate, I'm absolutely a believer now.

Edited by Wally
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I only do a vertical takeoff from ad hoc LZs. I always try to guard against the most likely thing to hurt me. From a place where I'm certain there are no wires, engine failure comes nearer the top of the list. But from a place I've never been, wires are at the tip-top. They're everywhere, and can be impossible to see from some angles. It's true that there is the possibility of an engine failure during the vertical ascent, but hitting wires while moving horizontally is a greater possibility. Making vertical takeoffs and slow steep approaches is the best way I know to minimize wirestrikes, and wires are absolutely the biggest menace during scene operations, especially in the dark.

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If you fly EMS, do a vertical takeoff ALL the time. Get good at it. Make it normal. Do it from the ground without a hover.

 

EMS helicopters SHOULD (but most often don't) have HOGE capability for all phases of flight. I would make HOGE capability mandatory by regulation if I could. Yes, bigger twin-engines burn more fuel, uh, dollars. That said, get rid of the two engines and put one big engine in their place, and you'll have HOGE capability for less fuel flow and less money.

 

The last two EMS operators for whom I worked required a 150' vertical takeoff, followed by a climb on heading to 300' day and 500' night, before turning on course. Good policy.

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Good question tiger. I noticed but never really questioned why they did it.

 

Rupert: Do you know if that is a common policy among EMS operators? What if you're in the middle of the desert somewhere and there are no wires or anything else to get tangled up in? Were you allowed to deviate from that policy at all?

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Good question tiger. I noticed but never really questioned why they did it.

 

Rupert: Do you know if that is a common policy among EMS operators? What if you're in the middle of the desert somewhere and there are no wires or anything else to get tangled up in? Were you allowed to deviate from that policy at all?

Why would I do a vertical arrival / departure going into an airport? Why would I do one going into a hospital that I've flown into hundreds of times and is located above any obstacles? I would be putting everyone in an unnecessary danger by extended flight in the shaded region.

 

You choose the dept / arrv path based on conditions. For EMS, probably 80% of the time vertical is necessary.

 

I can't speak for other aircraft but with the 407 I always have HOGE capability, even in the summer. You wouldn't be able to do this job without it. No way the company is going to lose revenues because their aircraft doesn't have the power to get in and out of a scene site vertically through OGE.

 

I believe the last crash we had in EMS was a departure off a hospital where a 40 ft antenna was located a significant distance from the pad. Don't remember if the pilot was familiar with the area but he clipped the antenna. That's all in the task of doing a recon prior to departure and choosing a path based on that.

Edited by Velocity173
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The policy is the same for the company I work for. The takeoff profile depends on the takeoff location, as does the approach. I don't do vertical takeoffs from my base, from hospital rooftop pads, airports, or other places I'm very familiar with. The only purpose of the vertical takeoff is to avoid wires, and if I'm positive there are no wires, there are safer takeoff profiles available. Engine failures on takeoff are rare, but not impossible. Having one during a vertical takeoff from an airport could be embarrassing. I know how to perform a vertical takeoff, and I think I'm good at it, so I don't have to do one every time I take off. I do them from every ad hoc scene, though, because I'm afraid of the unseen wires. But I will know if someone has strung wires around my base, and I believe that the odds of someone putting them up across an active runway are very slim. As I've said before, I try to guard against the most likely mishap, and that varies with every takeoff and landing, and throughout every flight.

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  • 1 month later...

A vertical take off from your own hospital pad gets you high enough, quickly enough, to give more emergency landing and fly-away options. A normal departure maximizes your time over cars and people, with fewer options if your single engine, or one of your dual engines, quits. Do a vertical take off all the time, if power and weight allow.

 

A vertical take off, from the ground, at an airport, minimizes the time that your rotor wash interacts with parked fixed wing. The sooner you get out of ground effect, and keep climbing, the less damage to parked airplanes.

 

Type of engine makes a difference. Some older technology engines, with small compressors for better fuel flow (C28 comes to mind) will not tolerate a rapid N1 acceleration. Pull pitch smoothly, and as quickly as your engines and drive train will allow without failure or abuse, and go straight up and out of ground effect.

 

This also makes a big difference in dusty, snowy and otherwise dirty environments. The sooner you get out of ground effect, the less likely a brown out or white out, and the less damage you do to your rotor blades and etc.

 

A smartly-done vertical take off does not abuse the machine and does not correspond to cowboying. I don't mean yanking it up, but, rather, what you normally call a Max Performance take off, without the hover. From the ground with no dawdling. You gotta have the power-to-weight to do it, though.

 

Do it all the time, and especially under light-weight and non-demanding conditions, and you will find it much easier to do it heavy, in the dark, in the rain, with rotating beacons all around you and blackness above.

 

From the ground, pull collective, monitor N1, Temp and Torque for normal acceleration and limits. Go straight up until 50' above obstacles, or 150', transition to forward flight on heading. Day, stay on heading to 300' before turning on course; and, Night, stay on heading until 500' before turning on course.

 

Do it all the time, all the time, all the time, until it becomes totally normal.

 

This practice and procedure will save your bacon some dark and stormy night.

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  • 2 months later...

A vertical take off from your own hospital pad gets you high enough, quickly enough, to give more emergency landing and fly-away options. A normal departure maximizes your time over cars and people, with fewer options if your single engine, or one of your dual engines, quits. Do a vertical take off all the time, if power and weight allow.

 

A vertical take off, from the ground, at an airport, minimizes the time that your rotor wash interacts with parked fixed wing. The sooner you get out of ground effect, and keep climbing, the less damage to parked airplanes.

 

Type of engine makes a difference. Some older technology engines, with small compressors for better fuel flow (C28 comes to mind) will not tolerate a rapid N1 acceleration. Pull pitch smoothly, and as quickly as your engines and drive train will allow without failure or abuse, and go straight up and out of ground effect.

 

This also makes a big difference in dusty, snowy and otherwise dirty environments. The sooner you get out of ground effect, the less likely a brown out or white out, and the less damage you do to your rotor blades and etc.

 

A smartly-done vertical take off does not abuse the machine and does not correspond to cowboying. I don't mean yanking it up, but, rather, what you normally call a Max Performance take off, without the hover. From the ground with no dawdling. You gotta have the power-to-weight to do it, though.

 

Do it all the time, and especially under light-weight and non-demanding conditions, and you will find it much easier to do it heavy, in the dark, in the rain, with rotating beacons all around you and blackness above.

 

From the ground, pull collective, monitor N1, Temp and Torque for normal acceleration and limits. Go straight up until 50' above obstacles, or 150', transition to forward flight on heading. Day, stay on heading to 300' before turning on course; and, Night, stay on heading until 500' before turning on course.

 

Do it all the time, all the time, all the time, until it becomes totally normal.

 

This practice and procedure will save your bacon some dark and stormy night.

 

I know this thread is old, but wanted to chime in that I teach my pilots altitude over airspeed takeoffs under most conditions for many of the reasons listed above.

 

In theater, it was absolutely necessary to make approaches nearly vertical due to unknown obstacles in the unimproved LZs. Most importantly, it minimized brown out conditions that were par for the course, even in heavy dust, and assists with maintaining total aerodynamic force in the lift vector as the aircraft transitioned from OGE to IGE altitude to landing. For takeoff, it was a deliberate, positive increase in the collective as we browned out on departure and a transition to forward flight once above the dust cloud. I often landed in a tactical area of operations(TAO) that had multiple LZs within 100 -200 meters of each other, multiple wire hazards, and we would not have visual contact with the other departing aircraft until we cleared the dust cloud and then linked up at the start point exiting the TAO. UAV feeds were all we had to determine suitability of a landing area since an overhead recon wasn't possible due to surface to air threats.

 

I find it fascinating that some of the TTPs used in deliberate operations overseas are very similar to HEMS operations.

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Those TTPs are similar for good reason. In theater you had many hazards as you described when landing off airport. In HEMS those hazards are very similar. Brownout, wires, towers, obstructions, trees, bushes and on and on.

 

It is all risk management. When I take off from my base (at an airport) I don't do a altitude over airspeed take off. I do a normal take off as it's an airport with few hazards. I am at more risk of loosing an engine. However, off airport I am more at risk for hitting something rather than loosing an engine. Thus the change in landing and take off profile.

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A vertical take off from your own hospital pad gets you high enough, quickly enough, to give more emergency landing and fly-away options. A normal departure maximizes your time over cars and people, with fewer options if your single engine, or one of your dual engines, quits. Do a vertical take off all the time, if power and weight allow.

 

A vertical take off, from the ground, at an airport, minimizes the time that your rotor wash interacts with parked fixed wing. The sooner you get out of ground effect, and keep climbing, the less damage to parked airplanes.

 

Type of engine makes a difference. Some older technology engines, with small compressors for better fuel flow (C28 comes to mind) will not tolerate a rapid N1 acceleration. Pull pitch smoothly, and as quickly as your engines and drive train will allow without failure or abuse, and go straight up and out of ground effect.

 

This also makes a big difference in dusty, snowy and otherwise dirty environments. The sooner you get out of ground effect, the less likely a brown out or white out, and the less damage you do to your rotor blades and etc.

 

A smartly-done vertical take off does not abuse the machine and does not correspond to cowboying. I don't mean yanking it up, but, rather, what you normally call a Max Performance take off, without the hover. From the ground with no dawdling. You gotta have the power-to-weight to do it, though.

 

Do it all the time, and especially under light-weight and non-demanding conditions, and you will find it much easier to do it heavy, in the dark, in the rain, with rotating beacons all around you and blackness above.

 

From the ground, pull collective, monitor N1, Temp and Torque for normal acceleration and limits. Go straight up until 50' above obstacles, or 150', transition to forward flight on heading. Day, stay on heading to 300' before turning on course; and, Night, stay on heading until 500' before turning on course.

 

Do it all the time, all the time, all the time, until it becomes totally normal.

 

This practice and procedure will save your bacon some dark and stormy night.

 

Heartily disagree with "always vertical". Yes, some of the specific scenarios presented to justify a vertical are sound- if they apply. Otherwise, it's not so easy. Airspeed and altitude are energy stores with some ability to trade one for the other, but that's not universal. You can be high enough to gather a great deal of speed down without gaining enough airspeed or recovering enough rotor to help, especially given the lack of instantaneous reaction- hence the height velocity graph.

Use ground effect and the lack of altitude to gain airspeed, especially at or above max climb rate airspeed. You can use that energy to regain rotor and fly towards the most survivable landing point if single engine, and climb (fly away) if in a multi- the ability to accelerate, especially to Vx/Vy, is also an issue in planning the safest departure procedure.

 

Sometimes survival is all you'll get, period. If that means you "fly the airplane as far into the (survivable) crash as possible", that's what you do- sacrifice material before people.

 

Vertical departures have their place, but they are not a silver bullet.

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Well, I am glad to work for a company that allows for the pilot to make decisions based on the situation they are presented with. Saying you have to do a vertical take off all the time, even at an airport is not promoting risk management. I suspect that train of thought would change after a pilot has an engine failure on take off at an airport.

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It's simple. Scene site, I'm going vertical. You do it because the threat of hitting an obstacle is significant enough to warrant putting the patient/crew in the shaded region.

 

Areas I'm thoroughly familiar with and obstacles aren't an issue, I'm doing a normal departure and arrival.

 

If you lose your engine at 100 ft and zero airspeed, it's gonna hurt. No way you're getting out of that without damaging your aircraft. If I'm at an airport doing a normal takeoff, by the time I hit 100 ft I'm already approaching my min ROD auto airspeed. If I lose my engine then, I can extract enough energy to cushion and land no problem.

 

Even on arrival, if I keep my speed above ETL just as I'm getting into IGE, I might be able to salvage a landing in the event of engine failure. Not to mention I'm using far less power in doing that kind of approach. Coming into a hospital you're thoroughly familiar with at a 100 ft hover, you're putting people in an unessesary risk.

 

Another problem with the high vertical arrival/dept technique is during high winds you're putting yourself in a greater chance for LTE. At least a greater time frame in the flight envelope that LTE might occur.

 

Risk management. Think outside the box and choose the arrival/dept based on conditions.

Edited by Velocity173
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Risk management. Think outside the box and choose the arrival/dept based on conditions.

 

Like JD said, it sounds like some operators don't allow such thinking. I definitely agree that vertical TO/LDs have their place, but to require it all the time seems like a bit much.

 

If an operator had an SOP that required vertical TO/LDs at all times, even if you can clearly identify a path that allows for a normal TO/LD, how would you handle that? Obviously you don't want to go to the CP and start making a big fuss about it, but just rolling over doesn't seem very productive either...

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Like JD said, it sounds like some operators don't allow such thinking. I definitely agree that vertical TO/LDs have their place, but to require it all the time seems like a bit much.

 

If an operator had an SOP that required vertical TO/LDs at all times, even if you can clearly identify a path that allows for a normal TO/LD, how would you handle that? Obviously you don't want to go to the CP and start making a big fuss about it, but just rolling over doesn't seem very productive either...

If the company required vertical at all times then I'd abide by their SOP. I wouldn't bring it up as a recommendation to the CP either. He's well aware of what's in the GOM and he would've changed the policy already if he thought it unsafe.

 

While I believe such policy would be an added risk, it wouldn't be very high on my priorities when considering a company for employment.

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Well, I am glad to work for a company that allows for the pilot to make decisions based on the situation they are presented with. Saying you have to do a vertical take off all the time, even at an airport is not promoting risk management. I suspect that train of thought would change after a pilot has an engine failure on take off at an airport.

 

I see your point, and to a great extent I agree with it. I don't get all hung up on it though. The only time a vertical takeoff will be a greater risk is if you are in a setting that provides for a ground effect airspeed over altitude takeoff and there are low to no winds. Any substantial wind would be to your favor for taking you out of the HV curve for a vertical takeoff, which is far more often than not.

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I promote and develop pilot decision making and judgement and complying with company SOP/GOM.

 

In IHST/USHST interactions discussing accident causal factors, we have never reviewed a HAA/EMS accident that had an engine failure in the HV area as a causal factor that I can remember. There may be some!

 

So, I ask how many accidents were caused by striking an obstruction and how many were caused by engine failure during a vertical departure?

 

Have any of us following company departure procedures had an engine failure? How much time do we actually spend in the HV area during the vertical departure? Pilots certainly recognize and hopefully minimize time spent there.

 

Let me state that without having to follow a SOP/GOM - non 135 governed ops, I would make a risk managed decision for a departure dependent on SA of all contributing factors. I feel as pilots (PICS) this is where this thread originated and is a good discussion.

 

Mike

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Mike

I spend too much time "inside the knee", the base pad is a hover hole, 2 operations per flight, and almost half the transports are scenes, almost half my operations have a vertical instead of normal profile. This base is unique in the program...

But, the number of HEMS power failures in landing/takeoff is low versus blade strikes, from my observation, (engine failures that are catastrophic make the news, the successful landings don't) considering the nature of the operation.

Blade strikes are much more common, a fair percentage of which happen in the vertical process. The number of wires that are unseen on the high and low recon is scary high. That's enough for me to do a vertical anywhere I'm not immensely confident of clear transition area. "Immensely confident" means I've personally walked and carefully surveyed the transition area or somebody competent to put an airport or helipad has done so.

 

Off on a tangent-

I know lots of guys who didn't realize they had had an engine failure until after they'd spontaneously landed from low 'gunship' hover, and the collective was in their armpit. Engines don't always suddenly stop. Now consider that same scenario from a high hover, you've sucked all the rotor holding height or climbing, and the engine out horn comes on... You are going to spread the skids, at the very least.

The engine subsiding in a normal takeoff profile, however, ends up with the pilot lifting the nose to avoid the ground, the first step in an auto or aborted takeoff- all good.

Well what about the cars/people/airplanes around the aircraft having the engine failure? If one exercise some judgement and planned the track to minimise hazard, you are probably better off in a normal takeoff profile directing energy into a selected path (and having a survivable impact) than falling from a vertical onto the pad, potentially missing it or rolling off in the 'hard landing/crash' sequence that follows. After the first impact, it's all phyics.

Edited by Wally
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Amen, Wally. As I've said before here, I try to defend against the most likely thing that might hurt me. At a scene, it's unseen wires and other obstacles. At an airport, departing from a runway or taxiway, it's probably engine failure. Any time someone tells me that I should always do something, I immediately stop listening. Doing the same thing every time, regardless of the circumstances, is going to hurt you sooner or later. I follow the GOM, but I reserve the right to exercise judgement, and use my emergency authority if necessary. I use the takeoff profile that I believe, in the circumstances, will do the most to prevent an accident. That profile is not the same in every situation, and never is for any pilot. I don't get paid for flying, I get paid for using my judgement, and I try to use it on every flight. If the boss, or anyone else, wants so second-guess me, they're welcome to do so, but I always try to do things that I can justify later. I just don't think I can justify making a vertical takeoff from a runway. Nor can I justify making a normal takeoff from an ad hoc scene at night. One has to adapt to the current situation, or else one is not a competent pilot.

Edited by Gomer Pylot
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  • 3 weeks later...

I heartily agree with Gomer and Wally. The book that covers every possible scenario doesn't exist and never will. Competent pilots use their experience and knowledge of the aircraft systems/limitations and apply them to the situation at hand. Every time I get in the cockpit I ask myself, "What was the last mistake I made?"

 

There is no such thing as the perfect flight, all we can do is minimize our mistakes. (Wish I could remember who said that)

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