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collision avoidance

bweiss

bweiss

Well Known Member
I am investigating collision avoidance systems. Does anyone have experience with them, pros and cons. Specifically I am looking at the Traffic Scope and the Proximity Alert R5.
 
Trafficscope VRX

I bought a Trafficscope VRX off E-bay and love it. I use it every flight. It tells me when I need to scan more or change altitudes. I really feel blind with out it now.

I panel mounted mine and put the antenna right on the glareshield. It works great. See it mounted right under the Dynon EMS. Stub antenna on the passenger side glareshield doubles as a gunsight. :)

cbglxl2016zy7.jpg
 
bweiss said:
I am investigating collision avoidance systems. Does anyone have experience with them, pros and cons. Specifically I am looking at the Traffic Scope and the Proximity Alert R5.
Click to expand...

I have this one and like it, especially the price/performance.

I haven't connected it to ship's power yet, and I've noticed that it gets unreliable with low batteries ( I think it's seeing my transponder and giving me .1 mi, +100 feet, etc.)

As long as the batteries are fresh, however, the performance is excellent.

I paid $439 "show special" at OSH.
 
Traffic Scope VRX

I also have the VRX and like it a lot. It is wired into the audio panels aux in and the audio can be adjusted independant of the radio volume using the intercom volume controls on the audio panel. The VRX also has an aux audio in that I have audio from a Sirius Satelite radio which allows for an easy second input into the audio panel. Here is an example of an audio warning over the Chino area in L.A. The light outside is bad, the air is scuzzy dirty, and it is that time when traffic is hard to see. When the warning comes I'll look to see distance and whether traffic is above or below me and by how much. While direction is not a feature of this model a rapid counting down of the distance shows fast closure giving general direction info. Once I had used it enough to decide that I liked it a transponder spike antenna was mounted on the bottom of the airplane for best reception. In higher traffic areas or for takeoffs or landings it sometimes has to be put on mute in order to think with all of the warnings going off.

http://www.youtube.com/watch?v=yaji7_l7UE8

Best,
 
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How about these two

The two top brands from my research is:

#1
http://www.monroyaero.com/detect.html (ADT-300)


and

#2
http://www.zaonflight.com/content/view/2/1/

The monroy is more expensive but it has been recommended to me several time. I am going to get one. Monroy has an older model http://www.monroyaero.com/detect.html]ADT-200[/URL] you can get used on ebay for less. It gives just range no altitude.

All these systems use the transponder signal from the other aircraft. None of the systems give direction like true TCAS. Zaon has another model XRX that uses gives some general direction info, but I know nothing of it. It looks large, clunky looking and expensive.

You can't go wrong with the monroy aero units and the lady that says "traffic" has a plesent voice. :p
 
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I've always wondered about the utility of the less expensive traffic boxes (can't call 'em TCAS) that just give you relative altitude and "range". I suppose it's better than nothing, but having a relative bearing too seems like it would be a real plus. Not sure if it's worth an extra $1,200, though...

And how do they determine range? Is it from the delay between interrogation and response? Signal strength?
 
Range on these little boxes is NOT real accurate. They use relative strength of signal. Therefore an airliner with a lot of power output will show up as closer than it actually is. The big advantage by indicating in 0.1s of a mile is that you can tell if the traffic is getting closer or farther away. With units that only indicate in whole miles, the traffic will have to make a 1/2 mile change before the change will show up.
 
Good

Mel said:
Therefore an airliner with a lot of power output will show up as closer than it actually is.
Click to expand...

Good! I would want alot of warning if one of those big boys was getting near me.


Kent
 
I've been flying with a Monroy ATD-300 for about 3 years.

I find it indespensible, but not foolproof. It's like a second pair of eyes on board.

In transponder airspace, it will alert you to conflicting traffic, and you can determine if it's converging or diverging by observing the range indication. The relative altitude is very useful, but don't assume that 100' of clearance is enough!

The only 'bug' that I've experienced is whenever I'm over water, I get '2 miles, 0 feet'). This was originally very worrisome until I got familiar with it. I expect that it's the reflection of my own transponder signal off the water that it's picking up.

It's amazing how much traffic it picks up that I never see.

Vern Little
 
I just pulled out the manual (disk) on the trafficscope VRX and looked up some numbers. These are quoted from FAA AC 90-48C and show the real beauty of one of these passive warning systems. It takes 12.5 seconds from spotting an object to reacting and the plane correcting. (seeing object-.1 sec. Recognizing it as an aircraft -1 second , Recognizing a collision course-5 seconds, deciding to turn left or right-4 seconds, muscular reaction-.4 sec., aircraft lag time-2 seconds, all for a total of 12.5 seconds.) At a 360mph combined closure rate it takes 10 seconds for two planes to close one mile. Even with a weak transponder signal that doesn't give accurate distance due to the way the TPAS measures signal strengh will give 20-30 seconds of warning to the pilot. This is enough time to see the rapid counting down of distance and the altitude relative to your own. It's really pretty amazing to get a warning and have this happen. The first time for me was over the CA Central Valley and we were at 8500' heading basically NW. The naggy women that they used to record the messages started yelling and the countdown of distance was happening fast. The altitude showed that the other plane was 500' above us so we looked out and up slightly. Here came this V-tail right at our nose but with a 500' altitude advantage. We looked up through the canopy as he passed. The whole thing took seconds.!

I'm a believer in having one of these things. Before buying this one I borrowed the basic one that just had a LED bar and a beeper and it worked great too. Pick a favorite brand and model and use it, you won't be sorry.

Best,
 
I can't find...

Hi all.

I'm planning to install a collision avoidance system in my RV-7 and I'm looking at different systems.

I want a panel mounted system with audio warning.

I think I've seen a post here on the VAF forum about a system which gives you the three closest threats, relative altitude, range and climb/decend info.
I'm not able to find the post again, and I've tried google search etc, but no luck.

It's not the Proximty R5, not the Zaon, not the Trafic scope VRX and not the Monroy.

Is there any other new system out there or is my memory wrong?

Regards Alf Olav Frog / Norway
RV-7 finishing
 
These fish finders won't find all the fish in the sky

Just remember, these things only point out airplanes with operating transponders and there is a LOT of aircraft flying without such things, flying with them turned off, or broken.

You still need to look outside.
 
Good traffic avoidance ops

Fly high. Seeing aircraft can be difficult even when ATC points it out. Using flight following/traffic advisories adds some usefulness.
 
I'm now flying with a Zaon MRX and love it. One advantage it has over the Monroy is that it gives 0.1 mile resolution below 2 miles. Because of this, you can tell very quickly whether traffic is getting closer or farther away.
 
I have had the little Zaon MRX now for about a year. It is remarkably helpful. One doesn't realized how many planes one flies to closer than one mile, until you have a system to tell you. I have found its distance measurements quite good, with exceptions when one is banking sharply. I have not noticed a difference in how far it claims airliners are, either, as sometimes I can look straight up 1000' and see the belly of a NW jet, and the little Zaon is telling me 0 miles right when it should (it uses slant distance corrections, don't know if the others do or not). The manual that comes with the unit is absolutely top notch, as good as any manual I've ever seen. It explains in detail all the limitations, etc. One additional thing the Zaon has, which I don't believe the Monroy has, is internal barometric (altitude) sensing, which constantly compares it to the onboard transponder's mode c report. I believe it monitors up to 10 threats at a time.

Not having bearing information is really not much of an issue, as one can see the rate of change of distance (the tenth mile resolution is helpful, even if it isn't accurate) to know whether a climb/descent is in order.

The audio output of the Monroy is a voice, while the audio output of the Zaon is tones only. The Zaon is a lot less expensive.
 
Alex,
The MRX shows airliners closer than they are because distance is a measure of transponder power. Airliners put out more power so they show up as closer. Not a bad thing.
 
I have been flying with the Zaon XRX with the Garmin 396 interface. I just love the unit and the info it gives me. Without the interface I had to constantly look at the unit to see if it was displaying any traffic. I called Zaon and suggested that they add some tone to warn that traffic was being displayed. Now with the 396 interface, the 396 shows the traffic on the map page. Once it gets close, I get a popup window with distance rings and the audio warning. The traffic symbol give you altitude + or -, in relation to your aircraft, and also an arrow if the traffic is climbing or descending.

I have picked up traffic that I would have missed without it. I have even tracked traffic that I hear talking to ATC. A very important point with this system is that you check the compass and altitude setting once in a while to make sure it is correct. I am still learning the unit.

JF
 
This was just sent to our EAA chapter mailing list this evening:

NTSB Identification: LAX04FA095B
14 CFR Part 91: General Aviation
Accident occurred Friday, January 16, 2004 in Tehachapi, CA
Probable Cause Approval Date: 5/30/2006
Aircraft: Beech 95-B55, registration: N555RD
Injuries: 1 Fatal, 1 Minor.

A Cessna 180K and a Beech 95-B55 collided head-on during cruise flight over a valley, between 1,500 and 2,000 feet above ground level. The Cessna's right wing separated, and the airplane descended to ground impact. The Beech, which had been in a cruise climb, experienced a punctured windscreen and fuselage. The pilot made a precautionary landing without further mishap. The collision occurred on a clear day about 6 miles west of the Tehachapi Airport, from where the Beech pilot had departed. Neither pilot was receiving services from the Federal Aviation Administration. Radar track data indicated that the Cessna had flown in a southeasterly direction after departing the Bakersfield area. Minutes prior to the collision, the pilot changed to a northerly course. Seconds prior to the collision the pilot initiated a northeasterly turn. The Beech pilot had just configured his airplane for a cruise climb, and was flying in a westerly direction toward Bakersfield. The Cessna was flying about 135 knots, and the Beech was flying about 140 knots. The closing speed was about 275 knots, or just over 4 miles per minute. The Cessna was equipped with a Mode S transponder, and its signal was detected by Traffic Collision Alerting Device (TCAD) installed in the Beech. Seconds prior to the collision, the Beech pilot heard the audible "traffic" alert warning in his headset, and he observed an illuminated target in close proximity on the annunicator. The target was within 200 feet of his airplane's altitude, and in his 1 to 2 o'clock position. The Beech pilot reported that although he looked for the target, none was seen. The collision angle between the airplanes was documented. The impact was ascertained by fitting the Cessna's right main landing gear wheel in the punctured right side front windscreen of the Beech. As the Cessna's landing gear passed through the upper portion of the Beech's fuselage, the right wing's lift strut was lacerated upon impacting the leading edge of the Beech's vertical stabilizer. Thereafter, the Cessna's right wing separated. An evaluation of the pilots' visual angles revealed the airplanes were within each pilot's field of vision.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot's inadequate visual lookout during climb, and the pilot of the other airplane's inadequate visual lookout during cruise.
Click to expand...
 
And beware the FAST fish

N941WR said:
Just remember, these things only point out airplanes with operating transponders and there is a LOT of aircraft flying without such things, flying with them turned off, or broken.

You still need to look outside.
Click to expand...

Yes, definitely.

I've been flying with the Zaon XRX and like it. However, there seems to be quite a lag when alerting for fast moving aircraft like regional jets and military jets. The faster the aircraft, the more significant the lag. Don't expect the unit to warn you in a timely manner regarding military aircraft closing at high speed.

See and avoid.
 
redbeardmark said:
Yes, definitely.

I've been flying with the Zaon XRX and like it. However, there seems to be quite a lag when alerting for fast moving aircraft like regional jets and military jets. The faster the aircraft, the more significant the lag. Don't expect the unit to warn you in a timely manner regarding military aircraft closing at high speed.

See and avoid.
Click to expand...
Remember, these are "passive" units. They have to wait until the transponders are "pinged" by either ATC or a TCAS. If there are no TCAS in the area, you may have to wait til the radar sweep comes around.
 
When I redo my panel next winter, I'm going to add traffic. I've had a lot of close calls in the past two years. Of course, I've been flying a lot more since the Rocket's been done but it just seems that the cruise altitudes are more busy.
 
f1rocket said:
When I redo my panel next winter, I'm going to add traffic.
Click to expand...
More than once have I wanted to have one of the active TCAS units and wondered if I'm willing to pay $10k for it. Lots of people will naysay it, just look out the window, etc. However, that may not always be enough, and there are plenty of tombstones to prove it, GA, military and commercial alike.

Midairs are a low probability situation, but I don't know how low. Perhaps some numerical cost-benefit analysis would be useful. What is the numeric probability of a midair? What are the factors that increase risk?

TODR
 
I don't know what the probabilities are but I do know what I've experienced. I've had three instances in the past two years where I missed another airplane by less than a few hundred feet. All were during cruise and the traffic was oncoming or crossing at the wrong cardinal altitude. In each case, I just caught sight of the other airplane as it was closing, with only seconds to react. If I didn't see them, I would have missed them but it would have been closer.
 
f1rocket said:
I don't know what the probabilities are but I do know what I've experienced. I've had three instances in the past two years where I missed another airplane by less than a few hundred feet. All were during cruise and the traffic was oncoming or crossing at the wrong cardinal altitude. In each case, I just caught sight of the other airplane as it was closing, with only seconds to react. If I didn't see them, I would have missed them but it would have been closer.
Click to expand...
Yes, I know what you mean. I'll never forget my first view of an RV-8 from the air. I was transiting the area under the DFW Class B south of GPM/GKY over Joe Pool lake, at about 2500 ft on my second solo cross country. Never saw him until he pulled up an turned away from me. It would have been a near-head-on impact. He probably only saw me because I was in a totally yellow airplane. Scared the snot out of me, but the flight went fine.

(and if you're on the board and remember that day last June or so, thanks)

TODR
 
Thanks!

Hi Pete!

Thanks for your post! Yes, it seems that the VRX is the one I've been looking for!

Regards Alf Olav Frog / Norway
RV-7 Finishing
 
Too late and too early...

Hi all.

The Traffic scope VRX is for some reason discontinued. That's the info I got when trying to order one. Anyone know why??

Then I checked with Zaon about the status of their panelmounted XRX and it look like it's still a few moths away. (see their answer to me from Rachel Ballard below)

Looks like this time I was too late and too early...

I guess the only option now is the Proximity Alert R5 (if I want to have three threats displayed at the same time)
Or does anyone know about another product which can do that?

Regards Alf Olav Frog / Norway
RV-7 Finishing





Hi,

We are indeed working on a panel-mounted version of the XRX, but it's not
yet available. We've had some setbacks, but are still doing testing on the
product. Hopefully it will be available towards the middle of next year. I'm
sorry I can't give a more definite answer, but that's all I know as of right
now.

Thanks,

Rachel Ballard
(469) 916-6640 x309

Zaon Flight Systems, Inc.
15946 Midway Road
Addison, TX 75001[/U][/B][/I]
 
I can tell you the reason the VRX has been discontinued... it was our predecessor to the MRX/XRX split. SureCheck and Zaon are owned by myself and a partner. We designed and produced Trafficscope VRX (and TPAS before it) under the SureCheck name, but since SureCheck's founding checklist line was growing in popularity, it made sense to separate the publications from the avionics end. In 2005, when the VRX was replaced with the MRX/XRX, Zaon was formed. MRX took the basic functionality of the VRX and made it MUCH smaller, much more accurate and less expensive. At the same time, XRX took the improvements and added direction, which created a whole new realm for portable collision avoidance systems (PCAS) than had ever been seen before. The top of the XRX contains the directional antenna array... no external antennas to determine direction are needed. The footprint is actually smaller than the VRX, although the dome is taller.

Both units continue to sell very well with several thousand of each in pilot's hands since their introduction in December '05, but for different reasons. MRX was meant to be a traffic alerter, not a traffic pinpointer. The range and relative altitude do give an adequate sense of where the traffic is coming from, since the altitude is arguably the most important piece of information you need to avoid a collision (accidents only occur at your altitude!). The XRX can actually pinpoint traffic with amazing accuracy. It's the difference of a co-pilot yelling out, "There's traffic out there, and it's a threat" (MRX) or "There's traffic out there to your right... see it?" (XRX). It all boils down to threat acquisition time.

The MRX can be panel mounted just like the VRX, but it takes up much less panel space (there are some photos posted in these forums of panels with MRX units installed).

And yes, XRXi (the installed version of XRX) is coming soon...
 
MRX vs. look and see

I've flown with the MRX for the past year plus here in the NE. I wouldn't think of flying without one now. I scan all the time, I'm amazed at how often you never see the planes, even with ATC telling you where and what direction and altitude. So comparing with visuals, I'll take the MRX which will tell me if it's closing and what altitude. I can recall one of the few times it didn't warn me was a J3 doing a straight in without a radio when I was turning base, so scanning is essential. I probably look harder because of the unit, a scan usually turns up nothing, but if the MRX says it's out there you sure look harder until it isn't a factor.

I think the Beech waited too long, if it's getting close and within 200' change altitudes before it's too close. If there isn't much transponder use then it's likely you're in quiet areas and unlikely to see anything.
 
hevansrv7a said:
And that's when I'll order one.
Click to expand...

As I posted on another thread,the XRXi has been scrubbed for reasons of cost (overall installed cost to the end user has been deemed to exceed the tolerances of the majority of pilots in this target market) and due to the oncoming addition of a portable ADS-B add-on component.

Anthony
 
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