A UFO in the radalt?
 

I'll apologise in advance for this post. It's the only place I can think of where I might get an intelligent answer...

I have a guilty pleasure in watching "The Curse of Skinwalker Ranch". For those fortunate people who are unfamiliar with this location/series the Utah ranch in question, formerly owned by Robert Bigelow, is the site of numerous unexplained events including UFO/UAP sightings. For some decades Bigelow and a US government entity were engaged in an investigation there, now taken over by another investor.

I'll spare you an account of the preceding events but a decision was made to use the owner's helicopter to conduct measurements of various parameters - unexpected EMF and gamma ray readings etc - at various altitudes above a target location where bizarre events, some measurable, like magnetic anomalies, had taken place. This involved flying a roughly circular, tight track at a set of target altitudes - say 5000 and 10,000 ft above sea level. The ranch is, as far as I recall (?), situated at about 4000 ft amsl. Initially at about 5000 ft the radalt started emitting a warning bleep and read in the range 45-55 ft agl. This was persistent but occasionally stopped (they didn't as far as I recall, show the indicated altitude coincident with the warning's cessation).

Attempting to proceed to the 10K level, where in previous experiments various anomalies had been witnessed, this alert became very persistent, sometimes reading as low as 35 ft agl. The pilot became unsettled by this as the warning persisted whilst maneuvering and so they aborted the tests. The radalt, according to the pilot, had never before exhibited this or any other anomalous effect. There was no information - in the series at least - about any follow-up tests to clarify the status of the instrument: which, unfortunately, is almost a defining characteristic of the series. Ground observers with binoculars were unable to see any other vehicle - drones etc - which might have triggered the warning.

So, to those who know, how would you rate this effect on the "strangeness" scale? Or put another way, can you think of any circumstances (other then the Sod's Law effect) which might contribute such a phenomenon?

I'd get that dodgy RadAlt sorted.

In mapping UFO sightings, you’ll see a positive correlation between low levels of education/IQs and higher levels of UFO sightings.

Hmm, tricky decision when the rad alt starts to misbehave - do you :

A. Check the connections, the T/R and the aerial or

B. Assume it is alien interference.................

Lest it be misunderstood, the program is predominantly nonsensical with a few interesting oddities. That said, Robert Bigelow spent a lot of money and 20 years investigating the place in conjunction with a US government department; as far as I know a summary of the investigation has never been published. Odd, that. My question is simply what kind of fault would explain a malfunction like this, previously not manifest and apparently non-reproduceable at other locations? I know plenty about the irritating nature of intermittent faults from substantial experience of technology in a number of fields and I'm interested to know if faults of this kind in radalts are familiar? I've seen plenty of idiotic misinterpretations in this series (the chief scientist has a doctorate in astrophysics and consults for NASA...) so I'd like to know if there's a likely terrestrial explanation other than "technology sometimes malfunctions": I've already figured that out.

Some of the measured anomalies involve extreme shifts in the terrestrial magnetic field and spikes in gamma radiation way above background. I was wondering if the radalt system was susceptible to those kind of variations. Assuming, of course, all the metering instruments involved (tri-field meters, radiation detectors, analogue and digital compasses, magnetometers etc) aren't also exhibiting random bugs.

Could also be Angels ...or Ghosts. Americans see a lot of both.

I've ruled out Yetis, due to the altitude involved.

Interesting that all anyone can respond with is hilarious jokes about Yetis etc. Try reading the actual question rather than reacting reflexively to key words...I obviously overestimated the probable intelligence of contributors.
Let's leave it at that.

What were the design/cleared limits of the radalt? Could it be outside it’s cleared height range and catching spurious returns. Or just U/S.

Nah, must be UFOs.

Mog

I have flown a lot of survey towing a bird and using radalt to maintain AGL and can say that sometimes they do strange things usually solved by trouble shooting the antenna and wiring to the instrument.
On another job when approaching a certain airport we would usually get a false radalt warning for a few seconds on long final. We were flying over flat jungle terrain. We looked and looked but couldn’t find anything that would trigger a warning. We were at about 500 agl over the spot and radalt was set to 150. We used to refer to it as the “Tall Tree Checkpoint”
I have also seen radalt start painting the sea floor and not the water surface. Usually over shallow, clear glassy water over a flat sandy bottom with no swell.

In the case above I can see no reason why the pilot would become “Unsettled” and abort the flight because of an erroneous radalt warning while in VMC conditions.

Its definitely a cloaked UFO with a force field around it. I was flying an old Cessna once and ATC told me I had a radar return following me less than 100 feet from me. That was definitely a UFO too. Just because I had an analog transponder that when reset had the echo return disappear does not discount the likelihood it was a UFO and not dodgy electronics!

What are the possibilities that poor or faulty EMC protection allows interference on the RadAlt and/or gamma detector?

Other clue could be to look for an old stainless steel car on the ground.
Those pesky flux capacitors radiate a lot over all bandwidths!

I had a Rad Alt set off the height alarm when at 37000 as a DC9 flew under us.

It's them evil 5G towers.

Not only do they cause Covid-19 but the spectrum they employ encroaches into aircraft radalt frequencies.

Plenty of fresh papers on the subject around and the risk is actively being managed, a quick search found a simple reference.
https://www.aviationtoday.com/2021/0...sues-aircraft/

Aren’t these the genre of tv programmes that would have us believe that extraterrestrials travelled to the peoples living deep in the South American jungle 5,000 yrs ago, built some pyramids, then left to return during the early 13th Century when they used lasers to cut stones in perfect lines assisting the Inca masons to build more temples and settlements; then finally left leaving no other signs whatsoever of their visit… or anything to help advance their ‘development’… or technology to protect them from the Spanish?

Would these also be the programmes that tell us the same extraterrestrials visited the ancient Egyptians, built some pyramids in the desert at a time thousands of years before Cairo appeared and again left leaving no other signs of their visit?

4,500 yrs later humans developed the industry and technology enabling us to go from the first powered flight to the first landing on Mars in a mere 68 years (1903-1971) primarily, as the story goes, by a 9 year old James Watt watching his Auntie’s kettle boil back in 1745.

Just imagine what we would have been capable of if those same extraterrestrials had visited the developing civilisations elsewhere in the world at the same times and given us a little more knowledge than a few stone buildings and the odd light show!

To answer the question,
a. -♾
b. Rad Alts & wiggly~amps doing their ‘thing’.

I think we call that flouncing out of the room......:)

Because ignoring it would make for very dull TV.
Unless of course he was in a Robbie, but then he would have been unsettled from the beginning :}

The question was

Before answering the question I’d hazard a guess that posters have read the post…
‘The ranch is at 4,000’ elevation with the aircraft climbing above altitude 5,000’ looking for 10,000’, the radalt intermittently then persistently indicating 35’, which unsettled the pilot flying the ranch owners aircraft.’

One of maybe these options?
a. Rad Alts & wiggly~amps doing their ‘thing’.
b. Pilot not in full control of the aircraft.
c. Persistent ‘buzzing’ by another aircraft.
d. Extraterrestrial activity.
e. A good story to attract a tourist industry.
f. A story to attract a second documentary.

Perhaps it’s the way the post was written, containing a mixture altitudes, elevations and heights - I don’t think it’s the contributors that have that overestimated intelligence probability. :ok:

Because this genre of programme is based on artificially created suspense and drama! Just watch a clip on Youtube and looks garbage.

The OP might have had a more sensible response if teh thread didn't have UFO in the title!

Per the OP's request, we should keep this scientific.

Would anyone have data of a RadAlt overflying a location with a Sasquatch below the aircraft; then a second flight (over same area) without Sasquatch. We must have proper test and control groups.

Does the said sasquatch have a 5G mobile phone?
Is he wearing a tinfoil hat? (Can interfere with all the electromagnetical fairies)

Its a very long time since I did my Radar maintenance course, ( and it wasn't RadAlt's) but... I thought Radar Altimeters were usually specified for low altitudes say less than 2,500ft. So if operating at 5000 or 10,000ft then isn't it possible you would see false echo's that would appear to be much closet than they actually are. First transmit pulse echo would appear in the quite time of the 2nd or 3rd transmit pulse and be interpreted as much closer distance ?


Hutch

It's a distinct possibility. RAs use a system of frequency modulated continuous wave radar. A CW signal is ramped up in frequency and the reflected return signal differs in frequency based upon the travel time. So the system isn't range gated, where subsequent pulses can be spread out to avoid such misinterpretation. The failure modes would be something that a radar expert (which I am not) could expand upon.

I refer my honourable friend to my previous answer.

Mog

😂😂😂👍

Radalt is a tranceiver there can be an emitter in the vicinity which “fools” your radalt. I heard even 5G cellphone communications might cause these kind of issues!

https://tc.canada.ca/en/aviation/ref...asa-no-2021-08

Most rad alts I have flown with have a top of scale, beyond which the needle is hidden and an off or unlock flag when it is above its maximum height.

I dont think I have seen a helicopter radalt thats works above 2000' AGL. I am guessing because they are subject to error above this sort of value. Radalt unreliability is not uncommon for all sorts of reasons - eg it doesnt like wavy long grass. UFOs are likely to be rather a long way down the list.

Assuming the original poster is at all serious, this brings to mind a saying common in the medical profession: "When you hear hoofbeats think horses not zebras."

As the OP has hopefully learned from this thread, there are an awful lot of common reasons ("horses") for radar altimeters to read spuriously or erroneously, all of them clearly explainable by the laws of physics, and such events occur often enough, at all altitudes, to make extraterrestrial causes ("zebras") extremely unlikely.

At the risk of writing the glaringly obvious, it should also go without saying that "reality" TV producers and directors are exceeding good at, and quite in the habit of, making mountains out of molehills.

Ask an avionics engineer. He will confirm alien interference as there is nothing wrong with the equipment.

It would be pretty cool if the aliens made the rad-alt play the Doctor Who theme like a theremin.

It would also be cool if when starting up a helicopter it made the sound of VWORP! VWORP!

There is nothing wrong with equipment and it definitely is NOT alien interference.
Most Radio Altimeters are design limited for height range. Most will flag and remove the height indication when beyond design limits, but not all. Some use different FMCW processing techniques to provide limited “look ahead” features.
Some Radio Altimeters designed for special applications such as guided weapons and military aircraft use PCM instead of FMCW. These can also have different range design features. These are by definition much more expensive and PCM altimeters are not common in civil aircraft although I have seen them installed for special operational applications.
Many are unreliable overwater particularly if the surface is flat calm, the same can happen over reflective sand based terrain. Antenna position and in particular antenna spacing and surface induced discontinuities are optimised for individual aircraft and are or should be in compliance with the equipment manufacturer installation specifications. There should be FM Supplements and or operating instructions for individual aircraft.
Sincerely, Avionics Design and Systems Integration Engineer.

Too high or too low?

FAA Warns Of 5G Effects On Radio Altimeters
 

And here

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