Is "flying under the radar" a myth?

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soin2la

soin2la

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For all you aviation people, does this pass the smell test?
https://globalnews.ca/news/7155762/bc-plane-still-missing-fraser-river-search/
Missing for a month.
Zero debris.
Populated flat lands.
One “witness.”
Two known, but unnamed people onboard.

Can a plane at an altitude of 60 meters, 196 feet, really be under the radar? If so, it could cover a lot of ground in a short time, without anyone on the ground really noticing.

What do you think? A pretty well planned disappearance?
 
I don't completely understand your question, but air traffic control radars do not always have coverage to the ground, especially in terrain. Most planes 'help' the radars by transmitting IFF to give controllers a hint where an aircraft is when radar returns are spotty, but the IFF is an RF signal that also has to be received by an antenna that may suffer the same blank spots. Aircraft 'fly below the radar' frequently, and if they disappear in that condition, the controllers only know where the plane was at its last reported location, its altitude, and which direction it was headed at that moment.

Greg.
 
Seems legit to me, although with the newer electronically steered radar arrays that gap is closing. The most questionable thing to me was the reported airspeed. ha ha.
 
FarEast1 said:
Seems legit to me, although with the newer electronically steered radar arrays that gap is closing. The most questionable thing to me was the reported airspeed. ha ha.
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Don't know what the "never electronically steered radar is".... never heard of it?


But, yes a plane can fly undetected in most airspace in the US at ~200 feet. They become visible to radar sites as they get close. And if their transponder is turned off, it's harder to identify the plane.


However, there's a lot of airspace, close to bigger cities when one will be in radar contact. And could be followed and found out who, if they landed at an airport where the radar could pick them up.
 
Greg;
The news report said the plane was travelling 80 knots (???) at 60 meters when it disappeared from radar.
I was wondering, if at 60 meters, it could continue undetected.
If so, in that area it could cover a lot of real estate, without being tracked or noticed.

Norther Spy has picked up on my thoughts.
 
Northern Spy said:
As if it never happened at all...
Click to expand...
Yes!
This is not a remote area; there are several thousand people living nearby, a dozen or more vehicles going by at any given time, but only one person “reports” this plane going in the river.

YXX (Abbotsford) is 10 miles away.

Names of those onboard are usually provided within hours, if not a couple of days, once families have been contacted. Crickets.

Sum sing wong.
 
soin2la said:
Greg;


Norther Spy has picked up on my thoughts.
Click to expand...

I'm not sure about that...

It may just be a business decision, legal recommendation, or cultural differences. It just strikes me as odd as not to not make a statement about the loss of a student, an employee, and an airplane.

“The initial flight plan submitted by the pilot did not take the plane in the vicinity of where it was apparently seen in the water” is unusual as well.
 
Seevee said:
Don't know what the "never electronically steered radar is".... never heard of it?


But, yes a plane can fly undetected in most airspace in the US at ~200 feet. They become visible to radar sites as they get close. And if their transponder is turned off, it's harder to identify the plane.


However, there's a lot of airspace, close to bigger cities when one will be in radar contact. And could be followed and found out who, if they landed at an airport where the radar could pick them up.
Click to expand...

Electronically steered radar is a thing. Used a lot in the military. Civilian ATC radar uses mechanically scanning radar. Most of the information visible to controllers is the result of a transponder interrogation. If the transponder fails or is switched off, planes are pretty hard to spot as a primary return unless the radar display is operating in the correct mode and the controller is looking for it. A large airliner is hard to track using skin radar skin paint (see 9/11). A 172 would be even harder.

Depending on the sighting of the radar there can be low altitude areas or areas blocked by terrain where the radar cannot see aircraft. In mountainous areas radar contact can be lost when the aircraft is many thousands of feet in the air.

In the text of the article, it doesn't actually say that the speed and position reports came from radar data.
 
I suspect the aircraft was tracked, I occasionally dabble in conspiracy theories. I was taught in the Canadian Navy that during naval military maneuvers we would not respond to mayday calls. President Trump declared Canada a national security threat so I'm guessing radar and drone flights along the border have been increased. I'm willing to bet that aircraft was on American military radar looking over the border.

https://www.mtlblog.com/news/the-tr...lly-calling-canada-a-national-security-threat
 
soin2la said:
Can a plane at an altitude of 60 meters, 196 feet, really be under the radar? If so, it could cover a lot of ground in a short time, without anyone on the ground really noticing.

What do you think? A pretty well planned disappearance?
Click to expand...


Ahem, let me share forty years of air traffic control experience, and 50 years of flying, including some familiarity with the area under discussion.



Flying under the radar is a thing. Radar is a "line-of-sight" device, profoundly affected by terrain and the curvature of the earth. Even in flat terrain, one doesn't have to be terribly low to be invisible. I can no longer find the momograph I used to site the one short-range radar for which I was the project manager, but as I recall the calculation, the "radar horizon" is 1.2 x square root of the altitude or at 196 feet altitude, roughly 16.8 miles, adjusted for the height of the antenna, of course.


The fact that they know the altitude makes it clear that it had a Mode C transponder, which transmits that info constantly, even if there is no contact with ATC, but it is subject to the limitation above.


I didn't see any indication in the story about where the airplane was seen going into the river, but immediately north of the Boundary Bay/Abbotsford plain, the terrain rises near vertically thousands of feet. It would be normal for the airplane to disappear in the Fraser Gorge.


In short: flying under the radar is a thing and the most likely explanation. When you hear hoofbeats, think horses, not zebras. :socool:
 
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I once talked to a gentleman in Montana (I was on Kodiak Island, AK) that was asking me about a helo he had on radar above the Aleutian Islands...he said it wasn't one of out H3 helos, it only had 4 rotor blades.
 
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psneeld said:
I once talked to a gentleman in Montana (I was on Kodiak Island, AK) that was asking me about a helo he had on radar above the Aleutian Islands...he said it wasn't one of out H3 helos, it only had 4 rotor blades.
Click to expand...


Absolutely nothing in my experience can explain this story. I have seen atmospherics which can cause "skips" off the troposphere; I once talked to a guy over Cleveland while working in Denver with 10 watt VHF radios which should have had 100 mile range, and very cold temps can cause radar to see over the horizon, like a fata morgana, but we're still talking about 200 mile radar looking out to 250 or so.
 
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90-92 on Kodiak....... And 2 arctic icebreaker trips during 84-86 had me in the Aleutians and Bering Sea.
 
AlaskaProf said:
Absolutely nothing in my experience can explain this story. I have seen atmospherics which can cause "skips" off the troposphere; I once talked to a guy over Cleveland while working in Denver with 10 watt VHF radios which should have had 100 mile range, and very cold temps can cause radar to see over the horizon, like a fata morgana, but we're still talking about 200 mile radar looking out to 250 or so.
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Over the horizon radar has been around for decades.

The big stuff doesnt use microwaves from what I understand. So line of sight isnt an issue.

Never could confirm what system it was that asked me that question or truly where it was...but it wasn't anywhere near the position of the reported helo based on that location.
 
<< over the horizon radar >>

...is about ballistic missile detection, not meaningful at helicopter altitudes, and the idea that one can count rotor blades on a long -range radar display is laughable.

Best explanation: You were talking to some kid with Dads VHF transciever.
 
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I don't believe so.

I also don't know what gear was being used, whether ground, airborne or satellite based....

I think the over the horizon radar was more than just ballistic missile finders...

From Wikipedia

The United States Navy created their own system, the AN/TPS-71 ROTHR (Relocatable Over-the-Horizon Radar), which covers a 64-degree wedge-shaped area at ranges from 500 to 1,600 nautical miles (925 to 3,000 km). ROTHR was originally intended to monitor ship and aircraft movement over the Pacific, and thus allow coordinated fleet movements well in advance of an engagement.
 
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I know that power line crossing from Glen Valley to Whonnock.
Fraser River SS
https://goo.gl/maps/zfit6FkzZmSVJ79RA
Fraser River NS
https://goo.gl/maps/heC9tU3KNXoByjsm8

The lines have the usual large red balls, plenty of them, but there is too mush bush to get a shot of them. Too much growth to see them from the road and I don’t see them on satellite.

Be interesting to know if the lines were inspected for impact.
 
soin2la said:
I know that power line crossing from Glen Valley to Whonnock.
Fraser River SS
https://goo.gl/maps/zfit6FkzZmSVJ79RA
Fraser River NS
https://goo.gl/maps/heC9tU3KNXoByjsm8

The lines have the usual large red balls, plenty of them, but there is too mush bush to get a shot of them. Too much growth to see them from the road and I don’t see them on satellite.

Be interesting to know if the lines were inspected for impact.
Click to expand...

From the report: The aircraft collided with the span between the North and the Middle suspension towers, which is 2077 feet long and was approximately 125 feet above the river at the time of the occurrence. The lowest line was damaged and was disabled by circuit protection (Figure 2).

There is a photo of the impact damage, but no balls in the photo.

125' above the river.

Wow.

Wonder if the flight school offers a barnstormer elective course?
 
Way back in the day I was in the USAF stationed in AK. I worked in the Inertial Navigation Systems (INS) in the RF-4C jets. We had one plane that kept dumping the gyro when it would do a certain maneuver. No way to duplicate it on the test bench so I talked my way into a ride in the back seat of that jet so see if I could get it to dump. I was on flying status at the time so it wasn't too hard to talk then into it.

So I got about a 1 hr ride and loved every minute of it. On our way out to the range the pilot took me for a "ride". About mach .8, 150'-200' above the ground.

It's amazing how fast stuff goes by when you're that low and that fast.

Once we got to the range we went into the maneuver that made the system dump. Straight up climb then over the top so we were inverted, then a slow roll over to right side up. I watched the gauges on the panel very carefully to see when it dumped and it did, right on schedule.

That was without a doubt the most exhilarating plane ride I've ever taken and to my credit I didn't need the barf bag.
 
Back in the late seventies early eighties I made the acquaintance of several pilots who often transported goods that they didn’t want officials to know about.

My understanding is that they flew as low to the water as possible in order to stay under radars horizon as long as possible. One of them disappeared on a trip and was never found. The story was that he liked to touch the water with his prop tips. Don’t know if that was true but they did fly very low.
 
That's really to bad that the instructor flew them into a crash. Yes, he had the responsibility of safe flight and there's a strong argument that low level flight can be extremely dangerous. It also can be fun.... high speed low level thru canyons, circles over your GFs house at 50 feet, high speed runway passes (not really too dangerous) and other low level stuff.


Overall, the radar discussion really has nothing to do with this story... it's just a fact that one can fly under the radar and is done all the time, and totally legal. If air traffic control can't see you, it's hard that they can point out hazards, not that they would have pointed out the catenary (assembly of lines strung between supports).


Unfortunately this is an accident caused by poor choices and ended up with horrible results. A big price to pay.
 
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