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Safety Discussion #2: Low Altitude Flight

Chris Hill

Well Known Member
I expect this to be a hot topic, so please abide by the following guidelines for this discussion in order to keep it civil:
1) If you know any of the people involved in the video or the accident, please do not identify them.
2) If you are any of the people involved in the video or accident, please do not self-identify.
3) Do not enter into personal debates/general philosophical discussion in this thread. Please use the PM system or start a new thread for those types of discussions.

The purpose of this discussion is to talk about the risks associated with the low altitude flight environment and how to mitigate those risks. For the purpose of this discussion, low altitude will be defined as less than 1,000ft AGL. Encouraging/discouraging flight in the low altitude environment is NOT the purpose of this discussion.

THIS IS NOT A LEGAL DISCUSSION. While some of these accidents may appear to be violations of the FARs, keep in mind this is a safety discussion and the video/accidents are presented as examples of scenarios where people have crashed in a low altitude maneuvering environment.

That being, said please read the following accident reports and watch the following video:

Accident #1
Summary: Low altitude flight (200-300 ft) resulted in controlled flight into terrain. This one might lend itself to a discussion of visual illusions at low altitude over water.

Accident #2
Summary: Low altitude flight (500 ft) resulted in controlled flight into power lines.

Accident #3
Summary: Low altitude flight (less than 900 ft) at night resulted in controlled flight into terrain.

Accident #4
Summary: Low altitude ?buzz? followed by a steep pull up resulted in out of control flight into terrain.

Accident #5
Summary: Aggressive low altitude flight resulted in out of control flight into terrain.

Treetop Flyer
Summary: Successful low altitude river run. What you can?t see here is what preparation (if any) was done prior to flying this route. I offer this as an example of someone who successfully flew in the low altitude environment and made it look easy. Don?t let a video persuade you to fly in a regime in which you have not properly prepared yourself to fly.

I could keep going?but I think these scenarios provide examples of the most frequent types of low altitude crashes (excluding takeoff and landing). My brief and unscientific estimation, based on looking at NTSB reports, is that this type of accident accounts for about 10% of all RV accidents. Regarding low altitude flight safety, there are probably 10 pages of legitimate discussion on how to reduce risk, so hopefully we can have a good discussion on ways to fly low altitude and do it safely.

I?ll start with some topics which might be addressed by some resident experts on the forum (not all inclusive):
Visual Illusions
Visual Illusions over water
Restricted visibility
Multi passenger Flight Characteristics
Night time low altitude flight
Bird Strikes

RVs readily lend themselves to low altitude flight because they are fast and have above average power to weight ratios. I suspect this leads many people to enter into the low altitude regime too casually from thinking that the airplane performance will keep them safe. Any time I am going to fly low, I thoroughly review the route of flight to check for obstacles. Start with a good map, and look for anything which might be a hazard to you on your route. Make a note of the altitude required to avoid those obstacles by a safe distance. Is it a good idea to fly near cell towers or radio towers? Nope. Not only due to the fact that the tower itself can cause you to crash, but the tower also has wires that help hold it up and which are very difficult to see until it?s too late. So first, start with a good route study on the ground. Once you have a feel for the path along the ground which you want to fly, go scout it out from a much higher altitude where you can see the whole picture around you and not have to worry about inadvertently crashing while you are checking the route. After you have done that, you are better prepared to decide if you really want to pursue flying low in that area.

Hopefully this is enough to get the discussion started. Remember, focus on techniques to be safe as you post in this thread.
 
"RVs readily lend themselves to low altitude flight because they are fast..."

Let's think about this- If faster is better for low altitude flight, when I feel like flying really low, I should leave the cub in the hangar and take the citation?
Terry, CFI
RV9A N323TP
 
Video of low altitude flight through river valleys scares the heck out of me. Valleys always have wires hanging from one side to the other, waiting to catch pilots who haven't seen them.

Not sure how electricity is distributed to farmhouses in the USA, but in Australia it's very common for utilities to use Single Wire Earth Return (SWER) systems.

SWER systems use a wire about the same gauge as fencing wire to carry 12.7kV on wood or steel/concrete poles about a quarter mile apart over distances of anything up to 30 miles.

The utilities seem to try their best to make the poles visually unobtrusive by putting them in groves of trees or scrub, or along existing fence lines where they won't interfere with agricultural machinery. And the wire is tiny, essentially impossible to see. Generally the only way you'll know they're there is by looking for a characteristic teardrop pattern around the base of each pole caused by the farmer's plough diverting around it, then by scanning out by approximately a quarter mile to find the next pole... And the next... And the next. But even that cue is absent if the poles are on fence lines or in trees.

And even then you won't know if you've found them all because the wires sometimes branch from poles to feed multiple nearby properties. Maybe you've missed a branch!

The upshot is that even flat, clear-looking, isolated terrain miles from civilization can be cross-crossed with wires on almost invisible 30 or 40 foot poles.

I know of at least one fatality caused when a pilot recovered an aircraft from an off-field landing in a valley. There was an unseen SWER line in his takeoff path; one pole was on the crest of the hill on one side of the valley, the next was on the crest of the hill on the opposite side, and the wire hung invisibly in an arc between them. Nobody knew it was there until the aircraft hit it.

So yes: low flying is so far below my personal minimums that it isn't even on the agenda. Except in very limited situations which I'm never likely to encounter in my flying career (such as well surveyed crop duster ops, perhaps), I just don't see how it can be done safely in my part of the world.


- mark
 
Video of low altitude flight through river valleys scares the heck out of me. Valleys always have wires hanging from one side to the other, waiting to catch pilots who haven't seen them.


- mark

This one almost got me as youngster. I was out on a training flight in a C-152 and impulsively dropped down into a river (just like the video). Luckily, I climbed slightly because of an upcoming bend because I didn't see the wires, that I missed by a few feet, until they went under me - talk about scary.
That cured me.

Good post Chris!
 
This is my regime.

Ok, time for me to chime in.

I make my living well below 1,000' and I'm here to tell you, after 43 years of doing this, it gets harder every year because of

A) In the mid-west mainly, the erection, overnight, of MET towers. These are Meteorological Evaluation towers that spring up overnight to evaluate the feasability of putting up a wind farm there...how many hours of such and such a wind strength, etc...they're just below the 200' requirement, so they don't have lights.

B) GPS towers in farming areas. I have had so many close calls with these 199', unmarked, grey towers that provide farmers GPS enhanced signals in order to have sub 2" steering accuracy (Yep, two inches!) for their autosteer device that steers their tractors and sprayers.

Our National Ag Aviation assoc is working to mark both the MET towers and these GPS towers with alternating red and white bands and also orange balls on those almost-invisible guy wires.

We've already had a fatality last month, when a 53 year old highly experienced ag pilot hit guy wires with an 800 gallon Dromadier.

You're taking your life in your hands when you venture under 1,000' out in the countryside where it APPEARS so safe and tranquil. That's exactly where you'll find MET and GPS towers.

I used to fly under bridges and cables on the Savannah river back in the '70's when I was young and bulletproof, in the Supercub that I sprayed a couple of lakes for mosquitoes with...but older and wiser shows how foolish low-level river runs can be.

Best,
 
The 12/93 edition of the RVator printed an interesting first-hand account of low flying, that had been sent in by a reader. This pilot claimed he had "on more than one occasion" flown 200 mile cross countries at 15 feet AGL and 200 mph, climbing only to avoid power lines or as required by 91.119. Presumably cell towers, MET towers, etc. were less of an issue then, but this account nonetheless made the hairs go up on the back of my neck.

The rationale for including this in the RVator was that some pilots will do this sort of thing even if told not to, so they might as well learn to do it right. Van, who wrote a short lead for the article, seemed a bit uncomfortable with this line of thinking, but allowed it to be published.

It seems to me that this example illustrates a general phenomenon that is often downplayed in safety discussions: the "fun factor" of RVs often leads to flight regimes rarely visited by the Cessna crowd. Ignoring this fact is unrealistic, but what is the right balance between safety and the realities of sport aircraft?
 
Thanks Pierre!

"You're taking your life in your hands when you venture under 1,000' out in the countryside where it APPEARS so safe and tranquil. That's exactly where you'll find MET and GPS towers."

The pilots that think rules such as FAR91.119 don't apply to them or are open to interpretation are the type of pilots that need them the most. Altitude is a lot like fuel - in most cases, the more you've got, the more options you have. Can I conduct an instrument flight with FAR minimum fuel knowing my primary and alternate are both at allowable weather minimums? Sure. Will I be comfortable if a don't have other options? Not a chance.
When highly experienced pilots such as Pierre warn against low flight (and do it for a living) it's time to pay attention.
Promoting or encouraging this type of flying, particularly amongst weekend pilots, is really contrary to the interest of safety.
Terry, CFI
Rv9A N323TP
 
Thanks Chris, I'm loving this new approach to talking about RV-specific accidents...keep 'em coming.

One thing I noticed...all five accident reports had two on board. Maybe some "watch this" showmanship involved? Just a thought...
 
I can see how the flying done in the Treetop Flyer video (which I love watching, by the way) could be done with some degree of safety, at least from wire and tower strikes. The first time I saw that I said to my wife, "I sure hope that guy regularly canoes or walks that area and knows for sure there are no obstructions. Otherwise it would be a crazy-stupid thing to do".

Stuff like that is far outside the envelope of anything I'd try. I can see how someone who knows the area very well, and checks it regularly, could do it without killing himself...

at least a few times.

If that big fan quits, though, it's going to get very, very uncomfortable in a big hurry.
 
I can see how someone who knows the area very well, and checks it regularly, could do it without killing himself...

at least a few times.

If that big fan quits, though, it's going to get very, very uncomfortable in a big hurry.

I'd say that 'Treetop flyer' could do this all day every day without incident, assuming no engine trouble. I don't see anything impulsive about it. If his engine quits, he's either going in the water, or pulling up and landing in the trees. In many parts of the country, there are areas where you're going in the trees (or other inhospitable terrain) no matter how much altitude you have. And have you ever seen the terrain Alaskans fly over? I'll take an engine failure over this creek bed over that, any day.

Yes, 'Treetop flyer' is sustaining some degree of risk higher than cruising at 2000' over the fields of Kansas. That's his risk alone, and he's got the skill and manages it well. The OP may construe this as off topic "ego", but it bothers me when people condemn others' flying as "dangerous" when it simply comes down to varying degrees of skill and risk tolerance. For some, there's nothing worse than seeing another pilot having fun, taking marginally higher risk, and displaying more skill than they have. Unless of course it's at an airshow, where it's perfectly acceptable to kill yourself. Just don't do it on your own out in the country without the proper FAA and ICAS waivers and paperwork allowing you to kill yourself. ;)
 
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The Big Trade

This safety thread shares a common theme with the previous one: "How much risk are you willing to shoulder in a tradeoff for thrills?" Risk assessment increasingly pervades every area of our lives today ... business, travel, health, diet, etc. It always about the security we're willing to trade away for, in general, short term excitement. As we all know, those are very individual/personal decisions. The key to making good risk-related decisions is to arm yourself (or in this case, others) with the information that enables sound tradeoff deliberations. Case in Point: the original post offers six cases that should help all of us when pondering low altitude or high-G (i.e. high risk) maneuvers.
 
...This safety thread shares a common theme with the previous one: "How much risk are you willing to shoulder in a tradeoff for thrills?"...

I?m not seeing it that way. The prior discussion concerned a required flight regime (the base/final turn), not thrill seeking. Flying enroute at low altitude OTOH, is a choice (at least in the context of this thread).

Concerning the thread in general:

I read an article in a magazine a few years ago concerning scud running and how to effectively deal with the situation if you did find yourself under a very low deck. It was not endorsing scud running as a navigation strategy mind you, just giving some pointers on how to save yourself if you were so unfortunate. Tips like ??if you need to fly under power lines, make sure you are as close to the pole as possible, not the middle, so you can avoid the sag in the wire?? Of course, this generated all kinds of letters to the editor complaining that the magazine was somehow encouraging the behavior? Based on that and recent threads here, I?m pretty sure I know how this one is going to turn out.

I?ll say that low flying is an endeavor some pilots take just for the sake of the thrill. Some people won?t understand that, but that?s just going to have to be enough of a reason. My take is that we don?t all fly for the same reason and leave it at that.
 
Counting Deer

I've read numerous reports of local flights enjoying the view on the ground, doing things like like counting deer, etc. How do you count deer unless you're fairly low? And if you're counting the deer, are you going to see obstacles, traffic, or problem terrain? The following is an NTSB report of an elk-spotting CFIT for one of the planes owned by the operation I rent from, just before I started renting from them.

http://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20070801X01081&key=1
 
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I'd say that 'Treetop flyer' could do this all day every day without incident, assuming no engine trouble.
Exactly my point.
I don't see anything impulsive about it.
Again... exactly my point. I got the impression from watching that this was an area he knew quite well, flies regularly and knows (to the extent it's possible) exactly what's coming.
If his engine quits, he's either going in the water, or pulling up and landing in the trees. In many parts of the country, there are areas where you're going in the trees (or other inhospitable terrain) no matter how much altitude you have. And have you ever seen the terrain Alaskans fly over? I'll take an engine failure over this creek bed over that, any day.
Regardless of terrain, I'll take an engine failure with as much altitude as I can possibly get. But that's beside the point, and I think we're in "violent agreement". The pilot in that video made a choice to assume the risk of his flying, and while it might be outside my personal envelope of what I'd do, if he's aware of the risks AND has enough knowledge of the terrain and obstructions, more power to him. It looks like an absolute blast.
it bothers me when people condemn others' flying as "dangerous" when it simply comes down to varying degrees of skill and risk tolerance. For some, there's nothing worse than seeing another pilot having fun, taking marginally higher risk, and displaying more skill than they have. Unless of course it's at an airshow, where it's perfectly acceptable to kill yourself. Just don't do it on your own out in the country without the proper FAA and ICAS waivers and paperwork allowing you to kill yourself. ;)
Again -- agreed. at the same time, though, there's a difference between "increased level of risk, with steps taken to minimize the risk" and "stupid stunt done with no preparation or reasonable expectation of a good outcome". Treetop flyer, if our assumptions are correct -- pilot accepts risk, takes reasonable measures, knows terrain, all's well. Stall/spin or hitting trees/cables after an ill-conceived low altitude, high speed pass... seems kind of stupid.
 
My 2 cents for today?First, I?m glad to see people posting who acknowledge their personal limits.. Sure, your limit is different from someone else?s, but why shouldn?t it be? We are all different. The most important part of flight safety and risk management is knowing your limits AND stopping short of exceeding them.

On to other fun?
Visual illusions come in a variety of flavors, but I think there are three standout cases where they prove especially dangerous for people flying at low altitude. First, there is the illusion of excess height due to featureless terrain. Featureless terrain is empty like open water, large open fields, and dark/unlit areas at night. Pilots who look down at the ground during low altitude turns or even straight and level flight will often get the feeling that they are much higher than they actually are. The effect is more pronounced when the pilot can?t see his aircraft shadow. You can defend against this visual illusion by looking out at the horizon line to pick up other details that help judge height such as trees or buildings.

The second type that stands out after reading these accident reports is that of G-induced overbank. Pilots flying low and looking left or right toward their shoulders while pulling G will have the perception that they are rolling out of bank. Without a good horizon reference, they will continue to roll into the turn despite the fact that they are rolling to 90+ degrees of bank. Low to the ground, rolling and pulling with bank angles greater than 90 degrees is frequently unrecoverable.

The third type is loss of discernable horizon. This can occur on hazy days, at night, or out over open water. Anytime you don't have clear sky/ground contrast, maneuvering in that environment should increase your riskometer a little bit, especially low to the ground. One of the worst moments in an airplane is when you realize that you're trying to pull up and get a climb going but your airspeed is increasing like crazy while your altimeter is unwinding like a looney tunes cartoon. Make sure you have a means to recover the aircraft to level flight if you become disoriented. Relying on the seat of your pants and external cues may not be enough.

Knowing these pitfalls of low altitude maneuvers is part of being able to mitigate that risk. Do you really want to be yanking and banking as the sun is coming up/doing down? What about over water? What about on days when there is no clearly discernable horizon? Are you going to be prepared to recover during maneuvers under G load while looking at ground objects?

How do you recover when you realize that you?ve become disoriented? Look at your attitude indicator first. Roll in the shortest direction to put your wings in less than 90 degrees of bank. Once they are less than 90 degrees of bank, begin pulling back on the stick while continuing to roll wings level. You are performing an unusual attitude recovery for those who are familiar with that term. Once you return to level flight, land and clean out your underwear.
 
My 2 cents for today?First, I?m glad to see people posting who acknowledge their personal limits.. Sure, your limit is different from someone else?s, but why shouldn?t it be? We are all different. The most important part of flight safety and risk management is knowing your limits AND stopping short of exceeding them.

On to other fun?
Visual illusions come in a variety of flavors, but I think there are three standout cases where they prove especially dangerous for people flying at low altitude. First, there is the illusion of excess height due to featureless terrain. Featureless terrain is empty like open water, large open fields, and dark/unlit areas at night. Pilots who look down at the ground during low altitude turns or even straight and level flight will often get the feeling that they are much higher than they actually are. The effect is more pronounced when the pilot can?t see his aircraft shadow. You can defend against this visual illusion by looking out at the horizon line to pick up other details that help judge height such as trees or buildings.

The second type that stands out after reading these accident reports is that of G-induced overbank. Pilots flying low and looking left or right toward their shoulders while pulling G will have the perception that they are rolling out of bank. Without a good horizon reference, they will continue to roll into the turn despite the fact that they are rolling to 90+ degrees of bank. Low to the ground, rolling and pulling with bank angles greater than 90 degrees is frequently unrecoverable.

The third type is loss of discernable horizon. This can occur on hazy days, at night, or out over open water. Anytime you don't have clear sky/ground contrast, maneuvering in that environment should increase your riskometer a little bit, especially low to the ground. One of the worst moments in an airplane is when you realize that you're trying to pull up and get a climb going but your airspeed is increasing like crazy while your altimeter is unwinding like a looney tunes cartoon. Make sure you have a means to recover the aircraft to level flight if you become disoriented. Relying on the seat of your pants and external cues may not be enough.

Knowing these pitfalls of low altitude maneuvers is part of being able to mitigate that risk. Do you really want to be yanking and banking as the sun is coming up/doing down? What about over water? What about on days when there is no clearly discernable horizon? Are you going to be prepared to recover during maneuvers under G load while looking at ground objects?

How do you recover when you realize that you?ve become disoriented? Look at your attitude indicator first. Roll in the shortest direction to put your wings in less than 90 degrees of bank. Once they are less than 90 degrees of bank, begin pulling back on the stick while continuing to roll wings level. You are performing an unusual attitude recovery for those who are familiar with that term. Once you return to level flight, land and clean out your underwear.

I agree with your post with one small change. In a UA recovery if nose low you roll to wings level and then pull. If you start the pull when the wings reach the 90 degree point you slow the aircraft roll rate and are making a rolling pull out which reduces your G available before aircraft damage occurs substantially. I was always taught taught roll to wings level then pull. The faster roll rate and higher available G will produce less altitude loss then a rolling pull.

George
 
Not a factor for Pierre but logging cables also pop up overnight in the mountains. Very difficult to see.
I bet cell towers are a pain for Pierre. There are a bunch of new ones near me but they are camouflaged to blend in with the surrounding area. I suspect above a certain height level they can't camouflage them but even a short one could be a big issue for someone doing what Pierre does especially if its painted and designed to blend in with the background.

George
 
How low is low?

It seems everyone here is talking about low flight as being something below a couple hundred feet. I think this also applies to higher altitudes. To me low flight is any altitude where if you get in trouble, things could get hairy quick. A case in point, a few years ago a Los Angeles pilot was returning from Mexico. He didn't think he needed to get fuel in Mexico so he left with less than half tanks. He flew up the coast and around Newport Beach he kept low (1500') apparently to avoid talking to the Class C controller. It was getting dark. He ran out of fuel and was too low to make the Class c airport. Tried to land on the beach but touched down in the surf zone, not in the deep water or the sand. The plan flipped over, the canopy could not be opened and they drowned. In this case 1500' was too low for being at a low fuel state, at night, over a densely popluated area. I think low is all relative. JMHO
 
It was pretty obvious that the pilot in the video was very familiar with the river and its environs. There is a short stretch of a few miles along the Chattahoochee River north of Atlanta where it is fairly wide and free of power lines that I have flown along at low altitude, in a slow, thus tighter turning, airplane, but below treetops/hilltops only at a couple of spots. There is a highway bridge at the end of the run, which requires the pilot to climb before reaching it, which is why it is a short stretch.
Bottom line, for me, in this situation is to be intimately familiar with the area in which you plan to fly at low altitude.
One thing I would ask the guy in the video is "What happens when you meet someone else doing the same thing in the opposite direction?" Not much escape room there, and not a lot of forward visibility at some of the tighter turns.
 
Still Valid

"There are "Old Pilots" and there are "Bold Pilots", but there is not such thing as an "Old Bold Pilot".

As one who spent 30 years and 10,000+ hours in helicopters, with a lot of it in the dead mans curve or below 500 ft agl it's just not a healthy thing to do in fast airplanes in my opinion.

I am still learning how to deal with nose bleeds when flying above 1000 ft.
 
+1

MET towers and new GPS towers also "spring up" overnight!

Ask me how I know.:eek:

Best,

My boss continually warns me that the towers Pierre refers to indeed DO spring up overnite, and of course these are just high enough to catch the props. Dang near invisible..

Part time, I spray for mosquitoes, using a turbine twin Beech. The ideal altitude varies with wind, but seems 150' is about right most of the time. We are out there at dawn, and we spray right up to the waters' edge. Neither of these factors promotes visibility.
This aeroplane is not maneuverable during the first 45 min of work: 11500# at t/o; these ships grossed at ~9000# from the factory.

Another caveat is the power lines: you can't really see the ground line that runs along the top. So, the survival tip there is to cross any high tension line at the towers - not between.

If this isn't enough to turn you around, there are BIRDS at lower altitudes. LOTS of birds. In big FLOCKS! Heck, I'm spraying over swamp, more or less! DOH! Feels like very accurate German flak at times...

So, if you are sure where the obstacles are, I guarantee you do not know where the BIRDS are. And, some of those are kinda hefty - it is not a good day when you take one of those critters out. They will knock a light bar clean off the plane...what if you are in a plane with no light bar? Bad juju...

Carry on - carefully!
Mark
 
Surprises can occur at low altitude at almost any time. I remember once many years ago carefully planning a flight in Egypt. We had all the briefings on where we could fly and not fly including altitudes. Took off with my wing man and flew the flight as planned. In the desert near the valley of kings we hit the biggest antenna farm I have ever seen. We were at 540 knots and 500 feet. Some of the antenna were at least 2500 feet high. Both of us slalomed through the 30 plus antenna like Franz Klammer on a downhill run. Popped out the other side shocked we did not hit anything. Landed to find a reception waiting for us. Angry Egyptians demanding to know why we had flown through their most secret installation. We asked why they did not tell us the area was restricted in the briefings or show it on the charts. A red faced angry Egyptian Colonel replied it was not on the charts or in the briefings because it was secret!!!
 
In my corner of the world it used to be perfectly safe to buzz along at 20 feet AGL. There are thousands of acres of open desert with very few (but well known) obstructions. However, thanks to the Greenies and their wind turbine scam, we now have these MET towers springing up like weeds all over the place. Several months ago I was doing some fuel flow readings, so had the autopilot engaged and running along at 3,000 MSL, which at my house is about 400 AGL, but diminishes due to slightly rising terrain to the west. After taking a quick reading and glancing up, I see one of these skinny little towers flash by slightly above and 50 feet off the wingtip. It wasn?t there a few days before. As much as I enjoy flying low and feel that I?m up the skill requirements, I?ve decided that a successful low level mission even in my own back yard depends way too much upon luck anymore. That takes the fun right out of it for me.
 
I'd say that 'Treetop flyer' could do this all day every day without incident, assuming no engine trouble. I don't see anything impulsive about it. If his engine quits, he's either going in the water, or pulling up and landing in the trees. In many parts of the country, there are areas where you're going in the trees (or other inhospitable terrain) no matter how much altitude you have. And have you ever seen the terrain Alaskans fly over? I'll take an engine failure over this creek bed over that, any day.

Yes, 'Treetop flyer' is sustaining some degree of risk higher than cruising at 2000' over the fields of Kansas. That's his risk alone, and he's got the skill and manages it well. The OP may construe this as off topic "ego", but it bothers me when people condemn others' flying as "dangerous" when it simply comes down to varying degrees of skill and risk tolerance. For some, there's nothing worse than seeing another pilot having fun, taking marginally higher risk, and displaying more skill than they have. Unless of course it's at an airshow, where it's perfectly acceptable to kill yourself. Just don't do it on your own out in the country without the proper FAA and ICAS waivers and paperwork allowing you to kill yourself. ;)

Beautiful! +1
 
Not yet...

I am not yet an RV pilot, but I will add my two cents from only a decade of low altitude helicopter flight.

I believe it all comes down to preparation. In the military we fly many hours a year, often fairly dangerous missions. Sure, we have accidents, but we have various procedures to mitigate those risks and learn from them. I think the key is in that last statement. Properly prepare for each flight.

I offer the following for you reconsideration.

1. We use a standardized brief guide every time we fly without exception. Using a guide helps you remember all the important things you need to discuss, especially when your mission is not one you conduct frequently. The brief always begins with a risk management discussion where we have a standardized list of hazards and we discuss methods to mitigate said hazards. Additionally, we have identified those specific hazards which are more likely to kill you. We assign points on a worksheet, as the number increases you are required to get more people (department head or even the CO) to sign off on the flight or you may not decide to perform that mission.

2. Emergencies. We brief all major emergencies prior to each flight in addition to how we will handle them in different flight regimes. For example:

"Fires. If we have an engine fire within 200 feet of the ground, either on takeoff or on final, we will land and fight the fire on deck. If it is above 200 feet we will ensure we are in a safe flight regime, pointed in the direction we want before we secure the engine..." Different aircraft and systems, but the point here is every time, BEFORE we fly, we discuss emergencies and how handling them will be different throughout the flight.

For low level engine failures I also brief if we have enough airspeed we will trade that for altitude...we discuss applicable airspeed and minimum airspeed. I also discuss increased birds/obstacles at low level and that a bird strike may cause a control jam, etc.
The point is that low level flight, as long as you are not breaking any rules, must be performed with forethought and planning so you are prepared for immediate response to emergencies.

3. Flying low over water or in terrain. If you don't do it regularly, you must remember that the "horizon" you think you are seeing very well may be a false horizon. Flying that low, you would want to be "outside" as much as possible, but if you are pulling the nose up to the "horizon" but it is actually a low level cloud or a river bank, you might still be nose down. We do this safely because we have 2 pilots...not a pilot and an observer, 2 pilots. One stays outside, one stays mostly inside, plus we have radalt, etc,etc.

4. If you can safely do it, do it. It is very fun. I have flown everything between a low hover and a high altitude, high mach run. I can say 150 kias 20 ft above the trees feels much faster and more visceral than 1.5M in the flight levels!
 
Low level flight has claimed many even with professional crews and planning. SAC (Stategic Air Command for you younger pilots) used to fly low level practice bomb runs so as to sneak under enemy radar. I recall this one B-47 crew that flew into an Aderondac mountain one night, the largest piece they found was a boot heel, they were going about 400 knots.

Low level flight always cranks up the risk meter, no matter how smart you are or think you are. I wouldn't do it unless there's money in it.
 
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just because you can doesn't mean you should-at least not without proper preparation

The majority of the examples weren't so much about illusions, etc., and a whole lot more about lack of discipline and preparation, with predictable results.

flying in and of itself requires training, preparation and currency to be done safely. flying low requires more specialized training and preparation, as the hazards down low are different than those up high. you mention g excess illusion, flat featureless terrain, g onset rate, sustained g's, etc. absolutely. there is also sun angle, cloud levels, trees vs bushes, small hills hidden in front of large hills, on and on. for those who fly low because they have to, there is quite a bit of specialized training. in the military that involves ground school on the illusions, physiological challenges, crosscheck, etc that are far too expansive to ever be addressed here. it then involves flying checkouts with stepped down altitudes. and of course in depth route study to look for all the towers, wires, structures we know about at least. and then there is the required currency interval. and they only go low for a reason, balanced with the risk to do so. even there, if the risk is too great, it isn't done.
even with all the specific training, there are numerous instances where military jets flying unplanned and impromptu low levels have resulted in tragedy, with the inevitable result making it harder and harder for those who follow the rules.

sure the FAR's allow certain behavior, and therefore technically it is legal. and sure, you can take your shiny little sports car airplane and do so if you wish. but you are very wrong if you think the only person harmed is you when you turn your joyride into a mess of congealed flesh hair teeth and eyeballs mixed with metal. the FAR's also require you to be intimately familiar with your flight for the day, expecting you to conduct thorough flight planning, etc. Diving into a valley and hitting charted powerlines sure makes it clear there wasn't good planning. The entire aviation community suffers a blow every time someone shines their a--, whacks it in, and makes the news.
every one of us loves to share our passion and joy of aviation with others. I would argue that means that especially with others we should strive for the disciplined professional approach aviation demands.

In Pierre's business, flying low is a requirement. And you can bet they are meticulous in knowing what threats are out there, at least those within their means to do so.

So I ask you to think about it. I totally agree flying low to the ground at high speed is a rush, but are you prepared for it, are you trained for it, do you know what you are doing and are you willing to accept the exponentially increased risk of operating down there? just because you can, does it mean you should?
 
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What is Low?

As a former Navy A-4 / A-7 guy who spent many hours on low level missions without incident, allow me to share a couple very important points about low level flying:
1) The risk factor is a function of the environment. Roaring low level through te deserts of CA, NV or Utah was a lot less risky than doing the same thing over farmland or rural populated areas. It's Pierre's tower thing.
2) The goal was to develop a comfort level through a step-down approach. We started at 360 Kts at 500 ft and worked down. Simulated nuc deliveries required 500 kts as low as you could go. Once over the Bravo 16 target at Fallon after 2 weeks of workups I was clocked at 520 kts at 35 feet. Normal low level routes were flown at 200 ft agl and 360-420 kts (made the miles per minute correction times easier).
3) I regularly fly my -8A low throgh the deserts near Death Valley. I have discovered an interesting phenomena - probably because of relative size compared to an A-4 / A-7 I'm nearly always lower (AFS-4500 give AGL readout) than I think. When I visually think I'm near 500 ft. AGL, I'm actually closer to 300 ft.
4) Always in the back of my mind at low level in an ever changing presentation - Where am I going to put this thing if the engine quits?
5) For me personally, the adventure of flying low over the desert is worth the admitted additional risk - your take may vary.
 
Not an RV or low altitude....but here's what happens at 185kts and 11000' when a goose makes contact with a Beech Baron. Pilot injured, but landed.

8fb929f7906ddb7e0b3e08d66a3d7471_zpse2b18520.jpg
 
I'd say that 'Treetop flyer' could do this all day every day without incident, assuming no engine trouble. I don't see anything impulsive about it. If his engine quits, he's either going in the water, or pulling up and landing in the trees. In many parts of the country, there are areas where you're going in the trees (or other inhospitable terrain) no matter how much altitude you have. And have you ever seen the terrain Alaskans fly over? I'll take an engine failure over this creek bed over that, any day.

Yes, 'Treetop flyer' is sustaining some degree of risk higher than cruising at 2000' over the fields of Kansas. That's his risk alone, and he's got the skill and manages it well. The OP may construe this as off topic "ego", but it bothers me when people condemn others' flying as "dangerous" when it simply comes down to varying degrees of skill and risk tolerance. For some, there's nothing worse than seeing another pilot having fun, taking marginally higher risk, and displaying more skill than they have. Unless of course it's at an airshow, where it's perfectly acceptable to kill yourself. Just don't do it on your own out in the country without the proper FAA and ICAS waivers and paperwork allowing you to kill yourself. ;)

Beautiful! +1

+1 Agree

risk management: they all exist
?flying
?flying single engine as opposed to twin (or more)
?flying recip as opposed to turbine
?flying at night
?flying IMC
?flying IMC with low ceilings
?flying over mountainous terrain
?flying over forest
?flying over open water
?flying single engine at night with low IMC over mountainous terrain
oh almost missed
?low level flying
 
Then, he heard the words "traffic, traffic" in his headphone. The pilot reported that he recognized this voice sound as being a "traffic alert" signal instigated by activation of the Ryan TCAD. The position of the conflicting traffic was displayed on the GNS 530. In response to the alert signal, the pilot glanced at the display and observed a yellow dot in the 1 o'clock position, relative to his airplane. The pilot stated that the display of a yellow colored dot indicated that the traffic was in close proximity to his airplane.

In a written statement subsequently provided by the pilot, he reported that the first traffic alert he heard was for traffic at his 2 or 3 o'clock position. He searched to his right and did not observe traffic. Thereafter, upon again looking again at the GNS 530's display screen, he observed traffic in his 1 or 2 o'clock position and close to the airplane symbol. He began a turn to the left. The pilot looked again at his 1 to 2 o'clock area and did not see traffic.

The pilot stated that he could not recall what altitude value was displayed for the approaching airplane. But, he recalled the altitude was not "zero zero." He believes that it may have been plus or minus 100 or 200 feet, but he did not have a specific recollection. The pilot did not recall seeing the numeric altitude value change when he subsequently glanced at the GNS's display.

The pilot reported that the collision avoidance system had no provision for resolution of the alert warning. He indicated that, on previous flights, he had observed the display of a "ghost target." He indicated that initially when a ghost target is detected, it might move from the left side to the right side or be in various positions until it finally is permanently displayed. Because of his experience with the unit, he was initially uncertain whether the depicted yellow target was to the airplane's right or left side.

The pilot stated that after he saw the yellow target, he then "looked around," but did not see any approaching aircraft. He indicated that the accident occurred several seconds thereafter. Upon further questioning by the Safety Board investigator, the pilot reported that less than 1 minute elapsed between the time the collision alert system first activated and the time of the collision.


I've posted this excerpt from the accident report because it illustrates a personal belief....that ADS-B traffic systems will give pilots a nice warm fuzzy feeling by making them aware of aircraft which have no chance of actually hitting them.....and they'll likely be head down, looking at the screen when they do get hit.

Returning to topic...in my part of the world (Deep South USA) the greatest "low altitude risk" extends up to somewhere around 2000 AGL....buzzards. They're everywhere.
 
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Then, he heard the words "traffic, traffic" in his headphone. The pilot reported that he recognized this voice sound as being a "traffic alert" signal instigated by activation of the Ryan TCAD. The position of the conflicting traffic was displayed on the GNS 530. In response to the alert signal, the pilot glanced at the display and observed a yellow dot in the 1 o'clock position, relative to his airplane. The pilot stated that the display of a yellow colored dot indicated that the traffic was in close proximity to his airplane.

In a written statement subsequently provided by the pilot, he reported that the first traffic alert he heard was for traffic at his 2 or 3 o'clock position. He searched to his right and did not observe traffic. Thereafter, upon again looking again at the GNS 530's display screen, he observed traffic in his 1 or 2 o'clock position and close to the airplane symbol. He began a turn to the left. The pilot looked again at his 1 to 2 o'clock area and did not see traffic.

The pilot stated that he could not recall what altitude value was displayed for the approaching airplane. But, he recalled the altitude was not "zero zero." He believes that it may have been plus or minus 100 or 200 feet, but he did not have a specific recollection. The pilot did not recall seeing the numeric altitude value change when he subsequently glanced at the GNS's display.

The pilot reported that the collision avoidance system had no provision for resolution of the alert warning. He indicated that, on previous flights, he had observed the display of a "ghost target." He indicated that initially when a ghost target is detected, it might move from the left side to the right side or be in various positions until it finally is permanently displayed. Because of his experience with the unit, he was initially uncertain whether the depicted yellow target was to the airplane's right or left side.

The pilot stated that after he saw the yellow target, he then "looked around," but did not see any approaching aircraft. He indicated that the accident occurred several seconds thereafter. Upon further questioning by the Safety Board investigator, the pilot reported that less than 1 minute elapsed between the time the collision alert system first activated and the time of the collision.


I've posted this excerpt from the accident report because it illustrates a personal belief....that ADS-B traffic systems will give pilots a nice warm fuzzy feeling by making them aware of aircraft which have no chance of actually hitting them.....and they'll likely be head down, looking at the screen when they do get hit.

Returning to topic...in my part of the world (Deep South USA) the greatest "low altitude risk" extends up to somewhere around 2000 AGL....buzzards. They're everywhere.

I agree. With no resolution the alert is useless until the target is sighted visually. A full blown TCAS system presents a resolution the same time the alert is given. Evidently ADS-B is not that smart.

With regard to the buzzards, this unusual cold air is keeping them down south, as soon as temps return to normal they will migrate north. We have them around here all summer, but not right now. :)
 
Ok sorry about the mis-information. I just got the pics and short description in the email yesterday. I also wondered how a goose cut such a perfect slot and where were all the feathers and blood.

But still a good photo concerning risk. Each of us has to decide what equipment is needed and where we are going to fly for our own personal safety/benefit/enjoyment.

I fly low quite often around here and at high speed. 200mph at 500' over the ice is pure therapy for me.....not many birds this time of year. Summer is a different story for me. Local conditions and terrain obstacle awareness dictate how low or fast I'll go. During races, I try to prefly the course at slower speed to evaluate things. During our briefs problem spots or abnormal conditions are discussed. If I haven't pre flown or something sticks out in the brief I may fly the course differently, including slowing down.....maybe that's why I've never won a race. :eek:
 
Ok sorry about the mis-information. I just got the pics and short description in the email yesterday. I also wondered how a goose cut such a perfect slot and where were all the feathers and blood.

But still a good photo concerning risk. Each of us has to decide what equipment is needed and where we are going to fly for our own personal safety/benefit/enjoyment.

I fly low quite often around here and at high speed. 200mph at 500' over the ice is pure therapy for me.....not many birds this time of year. Summer is a different story for me. Local conditions and terrain obstacle awareness dictate how low or fast I'll go. During races, I try to prefly the course at slower speed to evaluate things. During our briefs problem spots or abnormal conditions are discussed. If I haven't pre flown or something sticks out in the brief I may fly the course differently, including slowing down.....maybe that's why I've never won a race. :eek:

I knew what that photo was the instant I saw it on the front page, as it seems to come around about every other year. A friend of mine lost a friend and his airplane in that accident. Nothing against you at all Brian; I would have believed it too, had I not been familiar with the case. My beef is with the guy who started that urban legend in the first place. It's a good enough object lesson in traffic avoidance; why start a lie about a bird strike???:confused:
 
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I agree. With no resolution the alert is useless until the target is sighted visually. A full blown TCAS system presents a resolution the same time the alert is given. Evidently ADS-B is not that smart. :)


Its not so much the ADS-B isn't smart enough to provide RA because the informaiton needed.. location, altitude, speed, crs, time...etc are included in the TIS-(B)roadcast. Post-processing of TIS-B information is where the RA should and I suspect will eventually reside - although it will likely not be in coordination with the target as it is in TCAS-II.

I disagree the alert is useless without RA. What do you do when you visually see the target? You create your own RA. If I see a TIS-B target on my screen and cannot find it visually I can make a decision to alter my course, my altitude or my speed (or all three) to provide separation. I've done it many times during development and for real when the visual method fails.

All of our airplanes have a restricted Field of View (FOV). TIS-B provides the eyes in the back of our head, or below, where a visual scan cannot help.

It is a tool to be used within its design and intent. It has limits, so do our eyes.
 
I believe he was using TIS (Traffic Information Service), which is NOT ADS-B. TIS in my experience is allot better than nothing, but not as accurate as ADS-B as it relies on a target being interrogated by ground radar and then translating that information. This results in a delay that could cause several thousand feet difference between the displayed target and where the target actually is. Just this past week the TIS on my G1000 showed traffic ahead and to my right about 1 mile away and it was actually behind me and to my right. So it gives you a general idea and certainly has alerted me to traffic that I otherwise would not have seen.
Also, it does sometimes show your own return as traffic (that get's your attention, a yellow dot right on top of you), and there seem to be some areas where it will display "ghost" traffic that tends to be close and following you.
So, yes, it has limitations but I would be careful comparing it to ADS-B as it is not apples to apples. Just my 10 cents...
 
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