Safe/legal altitudes near the Chicago lake shore

polaris

polaris

Pre-takeoff checklist
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polaris
I was driving on Lake Shore Drive today just north of Navy Pier and did a double take as I looked out toward the lake. What appeared to be a light sport aircraft was wobbling around over the water along the lake shore... couldn't have been higher than 100 AGL. It seemed as if the pilot was doing turns around an invisible point just north of the Navy Pier Ferris wheel. For a second, I thought he may be ditching in the water, so I pulled out my phone to call 911. But it turns out he was just chillin by the water filtration plant around 100 AGL.

This got me curious about the whole "open water" regulation. Is the Chicago lake shore "open water" or is it a "congested area"? What is "open" water? Is there "closed" water? If the FAA just meant "over water," why didn't it just write "water" and not "open water"?

If the lake shore is indeed open water, what is a structure/vessel/vehicle/person that you can't get closer than 500 feet from? Does the man-made sea wall about a quarter mile off the shore of Lake Michigan count as a "structure"?

When I fly the lake shore, I like to stay out over the water around 1400-1500 feet MSL minimum. If flying down the west side, I stick to about 1800-1900 feet MSL and try to stay over the West Loop to satisfy the 2000-feet horizontal requirement from the taller buildings in the Loop.

Speaking of the 2000-feet horizontal/1000-feet vertical requirement, this puzzles me as well. When does "horizontal" turn "vertical"? Since the FAA does not specify "diagonal" distance, do I have to convert my calculations to horizontal if I am not flying DIRECTLY over a building? For example, I can fly 1000 feet DIRECTLY above a building, but if I am not directly over it, I have to be 2000 feet horizontal from it? So if a building's height in MSL was 500 MSL and you flew DIRECTLY over it, you can be at 1500 MSL. But if you move slightly over (for sake of argument, say 1 foot away from being "directly over"), you would have to be 2500 MSL to satisfy the horizontal distance requirement?
 
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polaris said:
I was driving on Lake Shore Drive today just north of Navy Pier and did a double take as I looked out toward the lake. What appeared to be a light sport aircraft was wobbling around over the water along the lake shore... couldn't have been higher than 100 AGL. It seemed as if the pilot was doing turns around an invisible point just north of the Navy Pier Ferris wheel. For a second, I thought he may be ditching in the water, so I pulled out my phone to call 911. But nope, he was just chillin by the water filtration plant around 100 AGL.

I am curious about the whole "open water" regulation. Is the Chicago lake shore "open water" or is it a "congested area"? What is "open" water? Is there "closed" water? If the FAA just meant "over water," why didn't it just write "water" and not "open water"?

If the lake shore is indeed open water, what is a structure/vessel/vehicle/person that you can't get closer than 500 feet from? Does the man-made sea wall about a quarter mile off the shore of Lake Michigan count as a "structure"?

When I fly the lake shore, I like to stay out over the water around 1400-1500 feet MSL minimum. If flying down the west side, I stick to about 1800-1900 feet MSL and try to stay over the West Loop to satisfy the 2000-feet horizontal requirement from the taller buildings in the Loop.

Speaking of the 2000-feet horizontal/1000-feet vertical requirement, this puzzles me as well. When does "horizontal" turn "vertical"? Since the FAA does not specify "diagonal" distance, do I have to convert my calculations to horizontal if I am not flying DIRECTLY over a building? For example, I can fly 1000 feet DIRECTLY above a building, but if I am not directly over it, I have to be 2000 feet horizontal from it?
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Hope that didn't interrupt listening to LSD by Aliotta Haynes and Jeremiah. :yes::yes: I love that song, about one of the greatest roads in the US.

As for your observation, I guess you just can't fix stupid. He'll be part of an NTSB report someday soon. Provided they recover his body and/or the aircraft.
 
polaris said:
Speaking of the 2000-feet horizontal/1000-feet vertical requirement, this puzzles me as well. When does "horizontal" turn "vertical"? Since the FAA does not specify "diagonal" distance, do I have to convert my calculations to horizontal if I am not flying DIRECTLY over a building? For example, I can fly 1000 feet DIRECTLY above a building, but if I am not directly over it, I have to be 2000 feet horizontal from it? So if a building's height in MSL was 500 MSL and you flew DIRECTLY over it, you can be at 1500 MSL. But if you move slightly over (for sake of argument, say 1 foot away from being "directly over"), you would have to be 2500 MSL to satisfy the horizontal distance requirement?
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I am not that familiar with the Chicago Area, but I have done airshows of North Beach back when Miegs was open.

But as for the 1000-2000 question.
Remain 1000ft above until you are at least 2000ft horizontal, then you can go lower.
 
BillTIZ said:
I am not that familiar with the Chicago Area, but I have done airshows of North Beach back when Miegs was open.

But as for the 1000-2000 question.
Remain 1000ft above until you are at least 2000ft horizontal, then you can go lower.
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Great. Thanks! Any tips on eyeballing 2000 feet horizontal?
 
nddons said:
As for your observation, I guess you just can't fix stupid. He'll be part of an NTSB report someday soon. Provided they recover his body and/or the aircraft.
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Why do you have to say that? You don't know what his intentions were or what kind of training he had.
 
MachFly said:
Why do you have to say that? You don't know what his intentions were or what kind of training he had.
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You're right. He could be a 30,000 hour LSA pilot. But his training or experience will mean little if his engine farts at 100ft AGL. He's going in the drink, in a really cold lake in November.
 
nddons said:
You're right. He could be a 30,000 hour LSA pilot. But his training or experience will mean little if his engine farts at 100ft AGL. He's going in the drink, in a really cold lake in November.
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I'm sure that's not what Lindbergh thought when he crossed the Atlantic with an engine much less reliable than the one in that LSA.
 
MachFly said:
I'm sure that's not what Lindbergh thought when he crossed the Atlantic with an engine much less reliable than the one in that LSA.
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Do you think Lindy had any illusions about surviving in the North Atlantic should his engine have quit? CL was attempting something that would advance the cause of aviation, the LSA pilot, not so much.
 
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MachFly said:
I'm sure that's not what Lindbergh thought when he crossed the Atlantic with an engine much less reliable than the one in that LSA.
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I'm not sure it's a good idea to use Lucky Lindy as a model for safety. Have you seen the film of that transatlantic takeoff? Blatant get-there-itis almost made that a very short flight and a very big fireball.
 
polaris said:
Speaking of the 2000-feet horizontal/1000-feet vertical requirement, this puzzles me as well. When does "horizontal" turn "vertical"? Since the FAA does not specify "diagonal" distance, do I have to convert my calculations to horizontal if I am not flying DIRECTLY over a building? For example, I can fly 1000 feet DIRECTLY above a building, but if I am not directly over it, I have to be 2000 feet horizontal from it? So if a building's height in MSL was 500 MSL and you flew DIRECTLY over it, you can be at 1500 MSL. But if you move slightly over (for sake of argument, say 1 foot away from being "directly over"), you would have to be 2500 MSL to satisfy the horizontal distance requirement?
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Could you explain how you get that interpretation from §91.119(b)? It says you can't go below "an altitude of 1,000 feet above the highest obstacle within a horizontal radius of 2,000 feet of the aircraft". So if you're within 2000' horizontally of your 500' building, you have to be at or above 1500'. If you're more than 2000' horizontally from the building, then the building doesn't affect your required altitude.
 
polaris said:
Any tips on eyeballing 2000 feet horizontal?
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You can't. If you're planning to cut it that close, measure it on a map first and identify landmarks that are at the appropriate distance.
 
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polaris said:
This got me curious about the whole "open water" regulation. Is the Chicago lake shore "open water" or is it a "congested area"? What is "open" water? Is there "closed" water? If the FAA just meant "over water," why didn't it just write "water" and not "open water"?
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Good questions. The FAA isn't very precise about open water. Presumably the idea is to exclude, say, a tiny pond or creek.

One way to pin it down a bit is to consider the FAA's designated SFRA VFR route for flying up the Hudson River past Manhattan. It brings planes within 2000' horizontally of +500' buildings, flying below 1300'. So if we assume that the FAA is not prescribing an illegal route, we have to conclude that the Hudson River qualifies as open water.
 
nddons said:
But his training or experience will mean little if his engine farts at 100ft AGL. He's going in the drink, in a really cold lake in November.
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Looks like he could maybe land in the adjacent park or road if they're not crowded. That's not unlike the standard VFR shore route past JFK at the maximum permitted altitude of 500'. If your engine quits, you either ditch or land on the adjacent beach if it's clear.
 
acrophile said:
Looks like he could maybe land in the adjacent park or road if they're not crowded. That's not unlike the standard VFR shore route past JFK at the maximum permitted altitude of 500'. If your engine quits, you either ditch or land on the adjacent beach if it's clear.
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That's downtown Chicago. The park has lots of trees, and Lake Shore Drive is always busy. Engine quits, he's going in the lake. Not a lot of glide available from 100 AGL anyway.
 
If you are lucky and the light at Chicago Ave is red, you will have about 15 seconds where you have a 2500' runway to land on (Lake Shore Drive northbound gets a left turn-arrow onto Inner Lake Shore and Chicago Ave for about 15 seconds, so no one is actually going northbound on LSD for that time). Then, immediately afterwards, you have about 15 seconds where Chicago Ave gets a green light into LSD. Cars will be streaming onto LSD but it's in single-file, so you can probably avoid these cars while landing since LSD has 3 lanes.

So if it's not rush hour (because during rush hour the light at LSD is always green), and you are lucky (about 30 seconds out of a 4-minute light cycle), you can probably land on LSD.

Can you tell I use that road way too much? Ha.
 
Now I'm just brainstorming for myself where we could actually land other than the cold, dark water, but... depending on the time of day and how cold it is outside, it is possible that the Lake Front Trail (bike path) is wide open. It goes right along LSD. It gets tricky because I would rather hit a car going the same direction as me than a jogger who isn't paying attention, but again, if you get lucky you might be able to land on the bike path. If you see human beings, you can ditch right along the path in the water. The human beings will see you and call for help.
 
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Where is RW to remind us it is mostly pilots narcing on pilots. They have us well trained for police state living.
 
How do you know that the guy was not in an aviation dry suit with PPE, had a safety vessel nearby and was performing a task that was specifically requested out over the water filtration plant area?
 
polaris said:
Now I'm just brainstorming for myself where we could actually land other than the cold, dark water, but... depending on the time of day and how cold it is outside, it is possible that the Lake Front Trail (bike path) is wide open. It goes right along LSD. It gets tricky because I would rather hit a car going the same direction as me than a jogger who isn't paying attention, but again, if you get lucky you might be able to land on the bike path. If you see human beings, you can ditch right along the path in the water. The human beings will see you and call for help.
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At that altitude (or lack thereof), how long would the pilot have to react? You've got some amount of time while the aircraft is decelerating from cruise to best glide, then a little more time to glide until you hit the water. I'd have to think that the deceleration time is pretty short, especially in an LSA. I've never pulled the power back to idle from cruise, but my instructor did. That was in a Grumman AA1B, and I had to lower the nose almost immediately. The LSA should have a little more time, but considering how little total time the pilot would have from power loss to impact, I'd think the only option would be to land straight ahead.
 
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FormerHangie said:
At that altitude (or lack thereof), how long would the pilot have to react? You've got some amount of time while the aircraft is decelerating from cruise to best glide, then a little more time to glide until you hit the water. I'd have to think that the deceleration time is pretty short, especially in an LSA. I've never pulled the power back to idle from cruise, but my instructor did. That was in a Grumman AA1A, and I had to lower the nose almost immediately. The LSA should have a little more time, but considering how little total time the pilot would have from power loss to impact, I'd think the only option would be to land straight ahead.
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If you aren't scared out of your wits there is plenty of time. Fear causes hesitation, hesitation causes your worst fears to come true.
 
FormerHangie said:
The LSA should have a little more time, but considering how little total time the pilot would have from power loss to impact, I'd think the only option would be to land straight ahead.
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Isn't straight ahead from engine failure at low altitude what we've been taught from the first time we put our butts onto the pilot's chair?

Didn't Sully demonstrate that straight ahead into cold water was sometimes the best alternative?

Jim
 
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Witmo said:
Do you think Lundy had any illusions about surviving in the North Atlantic should his engine have quit? CL was attempting something that would advance the cause of aviation, the LSA pilot, not so much.
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MAKG1 said:
I'm not sure it's a good idea to use Lucky Lindy as a model for safety. Have you seen the film of that transatlantic takeoff? Blatant get-there-itis almost made that a very short flight and a very big fireball.
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You can say the same about Alan Shepard, and a whole bunch of other people. The fact is that there are those people who choose to accept more risk and in the end often accomplish more, and there are those people who are so safety minded to the point where something a bit more dangerous than normal is a big "no." If it wasn't for those those people that chose to accept a bit more risk nothing would ever get done. Now think about all those people that tried to improve aviation, you think that was their first dangerous flight? Lindbergh used to be an airmail pilot, how many of us here would fly an airplane as reliable as his was in the same conditions as he flew in just so a fat man from Kentucky could get a letter from his girlfriend a few days quicker.
 
Bernouli and Goddard say gravity can go bleep itself.:lol:
 
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