Near Miss

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RB211
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Post by RB211 »

CAL wrote:What are the parameters on the typical tcas system?...I mean how far away.....etc.

I dont have one:) I guess when you only do 100kts you have some time to alter course
Sorry this is late CAL. Kinda got distracted trying to make sense out of ndb and didn't reply to your question.

Try this link and go to 'Operations' there is a good document detailing all you would want to know aboput TCAS, and then some!! :wink:

http://www.smartcockpit.com/
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Panama Jack
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Post by Panama Jack »

Piggy backing on that answer, different TCAS units have different ranges of display. The one on the aircraft I fly shows traffic up to 12 miles.

The TCAS' collision avoidance functions not so much based on distance, but rather on closure rates (time to impact). Most jet aircraft operate at an IAS of 250 knots below 10,000 feet (although sometimes it can be more).

Assuming you are flying head on with an Airbus at 100 knots indicated and him at 250 knots indicated at 5000 feet, your closure rate will be aproximately 385 knots True Airspeed. Thats at almost 6½ miles per minute! Remember that it is hard to spot traffic head on. Lets say that you can see traffic 4 miles away on a good day. However, both of you are going head on. The profile of a small aircraft, coming head on might not be seen more than a mile or two (another good reason to turn on your landing rights). Assuming the crew is super alert and sees you at 2 miles, there are a mere 14 seconds to properly spot you, identify you as a hazard, and take evasive action.

Both the mid-airs between a PSA Boeing 727 and a Cessna 172 in San Diego and the AeroMexico DC-9 and the light aircraft in Los Angeles make interesting reads.

By the way, don't think that turboprops go too much slower than the jets on descents. Dash 8's regularly true out at 250 KTAS or greater during descent. That can make for a closure rate head-on with a light aircraft at 6 miles per minute.
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Post by Right Seat Captain »

Cat:
I digress, I know. But I didn't notice if you had the same signature in the old forum, but I really like your quote. So true! :D
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Post by Disco Stu »

On a similar note, if you have TCAS, that doesn't excuse you from making 126.7 calls when you are decending out of the flight levels and then working out conflicts orally with conflicting airplanes.

Certain companies operating 1900s in MB and NWONT have bad habits of coming tearing down out of the flight levels with nary a call doing TCAS descents.

TCAS isn't a replacement for you eyes and position reports, merely a supplement.
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Post by Right Seat Captain »

ndb wrote:I find it annoying and useless when IFR pilots make position calls referring to obscure waypoints like "over XTZFR at Two point Five." It would be really helpful to us peasants not from out of town if position could be given in reference to a charted landmark (like the airport, a VOR or an NDB)-- ie. "10 miles southwest at two thousand five hundred inbound for landing"
Obviously you do not have an Instrument Rating. Unless I'm understanding the situation wrong, positions reports in uncontrolled IFR should be made at checkpoints, indicating the checkpoint's name. If you look closely at the Victor Airways on your VNC, ndb, you'll noticed the checkpints are marked with their names labeled. This should help you find that traffic. Good luck with the rest of your training!
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Post by cedarjet »

In uncontrolled IFR, when saying your position, it's nice to say the IFR and add in something for the VFR guys, like "5 to the south west inbound rwy 32" or something that they can get an idea of where we are, rather than "Xray inbound".
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I'd Rather Be Flying
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Post by I'd Rather Be Flying »

It seems as though I picked a good subject to touch on. Good comments everyone (well, most of you). The bottom line is safety; and by correctly announcing your intentions while in the air (at the right place and time) will help to prevent incidents or worse.

Stay alert (IFR or VFR). Use you XPR in uncontrolled airspace. Make the right radio calls. Fly safe.


:)
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Post by Right Seat Captain »

amen bro
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Leaky Float
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Post by Leaky Float »

NDB- I am fully aware that I am going to get pummeled for sticking up for you, however I feel obligated to do so. Some have been asking what you are doing to be so skiddish. What the answer to that is I haven't a clue.
I do however know my own behaviors rather well and there are times that I don't want ANYONE knowing where I am, or those to whome I am with. Why might one want the whole damn world knowing where you are every moment of your life? I charish deeply not only my own personal security, privacy, BUT the general safety of aviation as well. And once again, flying without a transponder (on or not having one) does not mean that you (we) are a danger to the public.


P.S. Cat- I almost always agree with you with your perspectives toward aviation, the Govt. and morons in general however I must disagree this time.

P.S.S- To the rest of you I totally understand your perspective, and I comend yaul on your ideals, however I must humbly disagree.
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Post by Airtids »

Leaky, I disaagre with you, but I also have to say that it looks like it's you that's got balls!!
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Post by Leaky Float »

Airtids- From my experience the size of ones balls is inversly proportional to the length of ones life. I don't have a death wish by any means however everyone needs a little time to ones self.

P.S. You must not be able to sleep tonight either! :roll:

Night
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Post by Panama Jack »

Leaky, I can appreciate where you are coming from. However, use of public airspace demands airmanship and consideration for others. In the case of mid-airs, it is not just your day you could ruin, but somebody else's.

Gliding in "F" airspace requires no transponder, radio, anything. I have no problems with this and also enjoy this past-time.

Likewise, although the mantra of the majority is otherwise, I like going SCUBA diving . . . . by my self. It is a great blast for me to slip beneath the waves, and enjoy the ocean, all alone. I recognize that I put myself at greater risk, but I also am prepared for it, don't take it lightly, and most importantly-- don't put others at risk by my pursuit. Worst case scenario-- rescue divers pull up 1 body that has been picked over by the crabs.
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Post by Cat Driver »

Leaky float:

Suprise, suprise....

You are correct, there are times and places where you can motor along in stealth mode and protect your privacy, I also do that, however that action must be weighed on where you are doing it and the possible affect on safety.

When operating in airspace where conflict with other aircraft is a consideration as far as the use of transponders is concerned we should always err on the side of safety...turn it on.

But you are correct our lives are becoming more and more regulated by those who wish to impose their power over us......

The use of transponders in known high use airspace is not an infringement on our rights , rather it protects our right to stay alive.... you just have to use good common airmanship when operating the transponder and not using it because you are either envious of better equipped aircraft or just plain moronic is not good airmanship.

Most here already know that, ndb is either a moron or a troll..... In my humble opinion of course. :mrgreen:

Cat Driver:
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Post by oldtimer »

Let me pose this question to the pro pilots out there. You are on the "company approved" approach to Rubber Boot airport out in the hinterland. You spot a target on the TCAS but nobody replies because the weather is below VFR. The traffic lands, you land. you find the airplane. You are ticked off enough to go over to the pilot and discuss his parentage. He cut you off on approach. He would't talk on the radio. you are ready to yell and scream. Your right seater tries to calm you down but with little sucess. The pilot is.
1. The most gorgeous chick you ever have seen. All sweet and demure, sorta like Brittney Spears.
2. The pilot is an ugly old boot.
Enter appropriate description.
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Post by Panama Jack »

Well Oldtimer, you got me in suspense . . . . .

Which one of the two do you really look like??? Please be honest and post a picture if possible. If you look like #1 I'll P.M. ya. :wink:
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Post by oldtimer »

I have been watching the discussion and most who are not raving have some valid points.Calling in over local landmarks is the favorite of VFR types because that is what they are familiar with. The IFR types always give a 5 letter waypoint ident because that is what is published. Trouble is not everone is familiar with these points. We always attempt to give a geographic position and a time to the airport. Certainly not having a transponder is not an issue that requires sever criticism nor is leaving it off all that bad as long as you are not in the vicinity of airports frequented by high performance airplanes. Just like the little old lady on the freeway, it is the difference in performance that is the problem. Chug along in your 172 @ 120 indicated, but just remember that the Metro I fly falls out of the sky at 140 indicated unless I am on final with everthing hanging. Same for the Beech 350. Nice and comfortable at 240 KIAS and 2000 ft/min down. Am I as safe descending into known or unknown traffic with those numbers as you are without a transponder. I would think that I am probabily as much if not more of a hazard than you are. Make you a deal. If you turn on your transponder and do not cruise VRF with your fin and rudder in the clag, hugging the base of the clouds I will slow down and reduce the rate of descent in VFR conditions near airports. And yes, we can "see" you without an altitude encoder. We just can't tell altitude so we will not get a TA or RA.
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Post by oldtimer »

Somebody asked me what we "see" on TCAS and what range. Answer. Range can be selected between 3 nm and 40 nm. A ring around the "airplane" (us) is 45 seconds before predicted impact for TCAS 1 and TCAS 11 so the area increases with speed. On the TCAS 1, we "see" a diamond. Open if the target or intruder is no comflict, solid if it is a caution and turns from white to yellow as it intrudes our "area of concern". Get within 500 ft and within 45 seconds, we get a "TRAFFIC TRAFFIC'" computer generated warning. WE can select various ranges, 3 5,10.20 and 40 miles. Just larger rings. We can select "above" where we can see traffic 2500 ft below and 7000 ft above, "below with the opposite numbers or normal where we see 2500 ft above and below. The number beside the diamont is the intruders altitude above or below us + for above &- for below. with an arrow up for climbing and arrow down for descending. fly level and the arrow disappears.
TCAS 1 only gives us a TA traffic advisory. TCAS 2 gives a TA and a RA resolution advisory. The electronic VSI will turn red either above or below the zero depending on whether TCAS decides we should climb or descend. Pitch the nose up or down to put the VSI in the green. Also get various verbal warnings. "CLIMD" DESCEND" " INCREASE CLIMB".
this is in part what happened to the DHL freighter that collided with the Russian airplane in Europe. ( Kill the ATC controller) apparently the DHL airplane responded to a TCAS warning but so did the Russian,in the same direction.
For traffic without altitude encoders, mode A only, we see the diamond but no altitude, nor will it change from open to solid and we will not get a TA
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justplanecrazy
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Post by justplanecrazy »

Leaky Float wrote:NDB- I am fully aware that I am going to get pummeled for sticking up for you, however I feel obligated to do so. Some have been asking what you are doing to be so skiddish. What the answer to that is I haven't a clue.
I do however know my own behaviors rather well and there are times that I don't want ANYONE knowing where I am, or those to whome I am with. Why might one want the whole damn world knowing where you are every moment of your life? I charish deeply not only my own personal security, privacy, BUT the general safety of aviation as well. And once again, flying without a transponder (on or not having one) does not mean that you (we) are a danger to the public.
I gotta say that I'm split on this decision. I think what Leaky Float is getting at is in some situations, you're not decreasing safety by turning off the mode C, you are only covering your own arse.

For 99% of the flying that I've done, I've kept the mode c on. I think if ndb is talking about flying up the Fraser Valley at 3,000 feet while dodging control zones, then yes he is worthy of every bad word directed his way. I mean to turn off your mode C while doing that, is the result of a minor anorism or some sort of mental meltdown.

On the other hand, there is that 1% of flying where turning off the mode C is probably a wise decision. I can relate to a time when I myself did this down south along the rim of the Grand Canyon. The Grand Canyon has a bunch of environmental or other sorts of protected zones all along the rim. Flight into the canyon itself is restricted and there are special charts that are published to try and guide confused tourists along their way. Well reading the charts and trying to decipher exactly where you are from 100 AGL is a little bit difficult to do. After about 50 bends, everything starts to appear the same. In this case we simply leaned over and flicked off the mode C. That way if we did happen to blow through some environmental zone, we wouldn't have the FAA screaming at us. In this situation I can't see how turning off the mode C would have created any sort of increase in danger for ourselves or those around us. If there are any planes with Tcas at 100 AGL, I think they have bigger problems to deal with.

I know that ndb isn't boosting his ratings right now but why don't we let him tell us where he is doing this before we right him off as mentally deranged.
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Post by Snagmaster E »

Now I'm coming into this late so tell me if it's been said.

Use all the tools available to you when you can. As for turning off mode "c" just to avoid being seen... If you're in a place where you are afraid that you might violate some protected airspace because of difficulties in low level nav along the grand canyon, well maybe you shouldn't be there in the first place. I'm not an expert by any means, but I know if I won't be able to perform the task while flying, then why attempt it if it isn't really necessary? Was it necessary for you to "accidentally" blow through some FAA restriced a/s? I don't think so. You don't want the FAA "screaming at you"? Then don't fly there. I don't think it necessarily made it less safe by turning off mode c (probably no difference), but if you turn it off just so you can do something to avoid the consequences, you'd better re-evaluate your attitude. "The rules don't apply to me".
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Post by justplanecrazy »

Snagmaster,

I see your point but you obviously have never seen the chart depicting the area. Throughout the flight we were 99+% confident that we weren't blowing through any airspace.

For the most part you can stick to the south rim and as long as you're not below the rim, you won't blow through any airspace. Although, there was one point where we had to cross the canyon and head North towards our destination. There is a tiny corridor that allows low level flight through the north side of the canyon but on either side there are restricted areas. We used every piece of navigational equipment available to us. Our VOR/DME (which wasn't reading accurately do to the low altitude) Our Compass, and Our map (which is pretty hard to read considering you have one variance in the land mass... the canyon. As well, you can only see a few miles of it at a time at that altitude.) We obviously knew where we were at any given point in time with relative accuracy but the airspace is so constricted that there was always that possibility that we might tag a corner of the restricted area. On the other hand the restricted areas weren't MOA's or anything of importance, simply environmentally sensitive areas. It wasn't a big deal if one of us happened to go an 1/8 of a mile into these areas. In other words it was simply native land where they have complained of the noise created by all the sight seeing tours.

Sure we could have simply climbed to a high enough altitude to be absolutely certain that we weren't slightly inside the sensitive areas but there was no safety issue involved and that would've ruined the whole point of flying along the Grand Canyon. I don't think that we were any less knowledgeable that someone else that isn't local and doesn't know the landmarks. The airspace was mainly created for the Air Tours not the few foreign pilots that they see flying through the area. Simply turning off our mode C eliminated the chance that we may get ourselves into some trouble for cutting a corner over Johnny long face.
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