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Unbelievable speed from my Uavionix Echo

Paul 5r4

Well Known Member
I wasn't sure where to post this and don't know what to make of it.
I was flying around the local area a few evenings ago, (South Alabama along the gulf coast). I noticed a target aircraft with a stinger so long it went off my ifly 740 screen. I tapped the target for the detailed information page and this is what came up. I know there's no way an aircraft was doing the speed shown. How can this happen? Can this be a glitch in the echo. It's my understanding that my ifly 740 is just reflecting the information provided by the echo. There is a restricted area just off the coast of Gulf Shores where the blue angels practice but this target is 7 miles east of the eastern part of that area.... and the top speeds of the F-18's are something like a 1000kts. The green dot is the Pensacola NAS just 15 miles ahead of the fast mover.... nothing about this makes any sense!
Any thoughts?

28svbqh.jpg
 
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I'm guessing speeds are restricted over land in that area, however given the proximity to both Eglin and Tyndall AFB's could be almost anything. I once was flying along the "corridor" in this area with flight following and was given a traffic advisory for an SR-71 (never saw it visually).

OTOH could just be a software glitch somewhere in the system that mis-calculated speed.....
 
If it would have been in one of the warning areas over the Gulf of Mexico just south of there then it could have been somebody from Pensacola, Eglin or Tyndall. A very standard rule is "No supersonic flight over land."

So more than likely a "glitch" somewhere.

:cool:
 
No fighter can fly at an indicated air speed that would achieve that kind of ground speed at the altitude shown by your display. The speed displayed is normally achieved at much, much higher altitudes by fighters (or SR-71's, F-111s, etc) Either your display is incorrect or there was something flying near you that is very exotic
 
If I remember right, military generally have a specific block of airspace where they can go supersonic, but they still need clearance.

An SR-71 is limited to 500 kts down low like that, if I recall.

Any idea what the mach number and airframe temperature would be if that were a real target? I'm thinking that the mach would be about 1.9 or so.

Dave
P.S. Whatever it is... something like it is my candidate for the RV-15.
 
I've seen similar glitches on my Skyview system, rarely but they have happened. Usually it shows up as you note...a target with a *GIANT* velocity vector. On mine, when they happened, it was only that way for a few seconds, maybe 10, then back to normal.

I suspect the ground segment of the ADS-B system is computing things very incorrectly and sending them up.

ETA: There are clearly some issues to be resolved with the entire system. I think we've all experienced the "ghost" target that is your own plane, popping up out of nowhere, the traffic announcement startling the **** out of you, and a "target" on your screen *at your altitude*, right next to you. Zoinks!
I've also seen a few times when a single aircraft is displayed as two, one on top of or right next to the other, same altitude, *similar* but identical velocity vectors (?), and so on.

Not sure who to report any of these sorts of things to, actually. Assuming it's not the fault of the avionics, is there some FAA office taking reports of apparently erroneous ADS-B data going out?
 
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The last couple of flights with my ECHO and 740b I have seen traffic show up that says it's at +136 and within my 3 mile " traffic radar alert screen. Being that high over my target ( 13600ft) , It gets my attention but I've got the iFly set to filter those out ( if +- 3500) . Just wondering why those would show up . Checked the filter setting on the iFly and found it to be correct. Not sure how or why it got thru. Visually, never saw any traffic but if altitude was correct, probably would not see anyway. Anyone notice anything like this?
 
Keep in mind that (even though they usually comply) military are exempt from "rules".
Sorry but the "no supersonic flight over land" is a self imposed military restriction, not a civilian one. As a USAF GCI Controller I made sure aircraft in my airspace and under my control followed it since my butt would also be on the chopping block.

Besides:
No fighter can fly at an indicated air speed that would achieve that kind of ground speed at the altitude shown by your display. The speed displayed is normally achieved at much, much higher altitudes by fighters (or SR-71's, F-111s, etc) Either your display is incorrect or there was something flying near you that is very exotic

:cool:
 
Well, there is 14 CFR 91.817 - Civil aircraft sonic boom:

https://www.law.cornell.edu/cfr/text/14/91.817

? 91.817 Civil aircraft sonic boom.
(a) No person may operate a civil aircraft in the United States at a true flight Mach number greater than 1 except in compliance with conditions and limitations in an authorization to exceed Mach 1 issued to the operator under appendix B of this part.

(b) In addition, no person may operate a civil aircraft for which the maximum operating limit speed MM0 exceeds a Mach number of 1, to or from an airport in the United States, unless -

(1) Information available to the flight crew includes flight limitations that ensure that flights entering or leaving the United States will not cause a sonic boom to reach the surface within the United States; and

(2) The operator complies with the flight limitations prescribed in paragraph (b)(1) of this section or complies with conditions and limitations in an authorization to exceed Mach 1 issued under appendix B of this part.​

This applies to civilian aircraft. It doesn't apply to military (Government) aircraft. :cool:
 
Your post seemed to indicate that there was no civilian rule that prohibited civil supersonic overflight over land.
No, I was only addressing supersonic flights over land by military aircraft and that it's a self imposed restriction not a prohibition. There are situations where supersonic flight over land by military aircraft is authorized, but not many. :cool:
 
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Yes, I know. We had one here a week and a half ago when F-15s were scrambled out of Portland to intercept the Q400 stolen from SeaTac. And we have had other supersonic intercepts in the Seattle area in recent years.
I imagine it was quite the "excitement". In 17yrs of GCI work I only did 1 supersonic intercept and it was during a training mission. I got to control 2 F-15's and intercepted 2 F-111's both flights supersonic over the Gulf of Mexico during a "Copper Flag" exercise. The intercept didn't take very long to say the least. :cool:
 
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