Midair Warning

On Wednesday, July 15, 2015 at 11:39:38 PM UTC-4, Darryl Ramm wrote:
On Wednesday, July 15, 2015 at 9:34:31 AM UTC-7, wrote:


TCAS is certainly impressive and proven technology, but I don't think you can claim that an F-16 with TCAS would have "prevented" this collision. We don't know the important details about how/why the collision happened. AFAIK it is still not clear if the Cessna 150 transponder was actually operating--was it actually turned it on? Was the encoder reading the correct altitude? Was the Transponder correctly set to Mode-C/S (not Mode A aka "ON" on many transponders... then a TCAS would not "see" the Cessna at all).


Just a slight correction. TCAS does indeed see mode A transponder returns. It obviously can not see the altitude of said transponder as there is no mode C altitude information being interrogated. So the TCAS will display the target range and bearing information and if there is a potential collision it will issue a TA or Traffic Alert audio warning and the target turns yellow. Since TCAS needs the altitude information in order to compute a climb or descent escape maneuver or RA Resolution Advisory, TCAS will not provide that as it would if the target were mode C equipped and operating. So the pilots eyeballs are the only defense. This is often frustrating as you can be flying in the flight levels and be get a TA warning for non mode C traffic in a airport traffic pattern 10,000' plus below. That said I'd much rather get the warnings and drive the pilots eyes outside and in the direction of the threat to scan all close altitudes than not know about it. Cheers.

Couple of points. As Kirk pointed out, and he is correct, IFF interrogators in fighters do not provide altitude information, only bearing and range. This system is also manual and needs to be activated to interrogate.

The military follows the rules more than many might think or want to believe. The only times they do not is when their TO's (POH) states the speed requirements, and they have a waiver. Also as mentioned, speed limits do not apply when they operate within the confines of MOAs, restricted airspace, warning areas or MTR routes. However, fighters must schedule MTR routes, and local FSSs are aware of the scheduled use of these routes.

As to ADS-B, working in DoD Acquisitions, I can tell you the USAF is trying to comply with this new requirement for all aircraft. However, an FAA mandate does not provide any funding, just like it doesn't for you either if they mandate transponder use for gliders. Trying to fund solutions for the military community is very problematic in the current budget environment, but the goal is to make it happen, it will just take a lot longer in the current budget climate if the military wants to keep its eroding capabilities over providing warnings to civilians while flying in the US for training missions.

FWIW, Garmin just announced the GPS-20A, a TABS-compliant non-certified ADS-B WAAS position source for $845 ($1225 with antenna and install kit). Whether or not we end up up having to deal with the ADS-B mandate, we really should be pushing the FAA hard to allow TABS equipment to be installed in certified gliders.

Marc

On Wednesday, July 15, 2015 at 12:11:49 AM UTC-5, WaltWX wrote:
If the FAA could only assure the gliding and GA community that equipping with transponders and ADS-B would provide avoidance of midair collisions, perhaps there would be more acceptance. Even with a transponder, aircraft collide with each other. TCAS on airliners (mostly) is the only system that seems to assure a resolution to collisions.

GA that predominantly fly VFR and gliders would gain the most from Nextgen improvements by preventing midair collisions.

It seems that FAA's main thrust with Nextgen (adding a second tracking ADS-B system) is for THEIR BENEFIT to control traffic under postive control (IFR or VFR Advisories radar tracking). That is the premise and main policy motivating this change to transponders everywhere and ADS-B.

BTW, I do have empathy for those wishing to stay in gliding at the lowest cost, raising their family and educating their children. Adding transponders and ADS-B doesn't seem to have a sufficient cost benefit. My particular financial position allows me to add that equipment.

Walt Rogers WX

Walt Rogers WX

Walt:

You've hit the nail on the head. The FAA wants us to spend all this money, but then they don't use the data. Right now, under the FAA rules, ATC can watch an airliner heading straight for a transponder equipped VFR aircraft and not even give the airliner a traffic advisory, much less a minor course deviation to avoid a potential collision. Everybody is putting their trust in eyeballs and TCAS.

Eyeballs don't work when you are dealing with jet traffic. TCAS also is useless when you have Military jets, who are exempt from ALL the rules, flying around at 400+ knots 500' above the ground without TCAS or ADS-B, and maybe not even an operating transponder.

Before we have any more FAA mandates, we should insist that all Military jets be equipped with TCAS and ADS-B just like everyone else, and that ATC (both civilian and military) provide active separation services for all IFR aircraft under their control to avoid any transponder or ADS-B OUT equipped VFR aircraft that are visible on their radar screens.

Once everyone (including Military jets) are ADS-B OUT equipped, we will have an environment where low cost ADS-B IN systems can provide very accurate collision warnings to VFR pilots, so we can actively stay out of harms way.

On Wednesday, July 15, 2015 at 11:58:46 AM UTC-5, Mike Schumann wrote:

You've hit the nail on the head. The FAA wants us to spend all this money, but then they don't use the data. Right now, under the FAA rules, ATC can watch an airliner heading straight for a transponder equipped VFR aircraft and not even give the airliner a traffic advisory, much less a minor course deviation to avoid a potential collision. Everybody is putting their trust in eyeballs and TCAS.


Care to provide a cite for that statement? Ever heard of flight following - or even used it?

Eyeballs don't work when you are dealing with jet traffic. TCAS also is useless when you have Military jets, who are exempt from ALL the rules, flying around at 400+ knots 500' above the ground without TCAS or ADS-B, and maybe not even an operating transponder.


Wow - so much BS in one paragraph, I'm impressed!. First, if you can't see an airliner coming towards you and avoid it, you should ground yourself (and not drive, either). Even F-16s are visible in plenty of time to avoid if you are actively looking. The real problem is the human eye and brain are not very good at the sustained task of visual lookout for ANYTHING. Second, since TCAS detects transponders, and ALL military aircraft are required to have their transponders ON when operating in joint civilian/military use airspace, TCAS is totally compatible with military jets (and many of the military transports have it also). Third, military aviation has even MORE restrictive rules than civilians, and military aviation is required to comply with civilian rules to the maximum possible when in joint use airspace. The only exception is speed, since some jets need to be above the 250 knot max airspeed limit down low - but that doesn't mean they are blasting around anywhere they want. VR and IR low level routes, along with MOA's, are other areas where some military flying will be fast and low - BUT THAT IS ALL TIGHTLY CONTROLLED AND SCHEDULED, AND YOU CAN FIND OUT WHERE IT IS HAPPENING BY CALLING THE LOCAL FSS! And finally, what military jet doesn't have an operating transponder? Again, ALL mil aircraft (including most UAVs) have transponders. Sure, it could fail inflight, but if it was broken before takeoff, that flight would not go until it was fixed - BECAUSE IT'S REQUIRED BY MILITARY RULES!

Before we have any more FAA mandates, we should insist that all Military jets be equipped with TCAS and ADS-B just like everyone else, and that ATC (both civilian and military) provide active separation services for all IFR aircraft under their control to avoid any transponder or ADS-B OUT equipped VFR aircraft that are visible on their radar screens.


More BS. Do you actually do ANY research before putting out this drivel?

Once everyone (including Military jets) are ADS-B OUT equipped, we will have an environment where low cost ADS-B IN systems can provide very accurate collision warnings to VFR pilots, so we can actively stay out of harms way.

Total, absolute BS. The time delay inherent with the ADS-B system, and the poor coverage at low altitude, makes it pretty useless as a collision avoidance system for military jets. Who, by the way, have a much better system (air-to-air radar, JTIDS, interrogators).

Will any military aircraft ever get ADS-B? Sure, airlifters and transports will probably get 1090ES so they can use international airspace. Fighters? probably not - unless it's a software upgrade to existing Mode-S transponders they now carry.

As usual, Mike, you are totally clueless.

Kirk
66

On Wednesday, July 15, 2015 at 1:24:31 PM UTC-5, kirk.stant wrote:
On Wednesday, July 15, 2015 at 11:58:46 AM UTC-5, Mike Schumann wrote:

You've hit the nail on the head. The FAA wants us to spend all this money, but then they don't use the data. Right now, under the FAA rules, ATC can watch an airliner heading straight for a transponder equipped VFR aircraft and not even give the airliner a traffic advisory, much less a minor course deviation to avoid a potential collision. Everybody is putting their trust in eyeballs and TCAS.


Care to provide a cite for that statement? Ever heard of flight following - or even used it?

Eyeballs don't work when you are dealing with jet traffic. TCAS also is useless when you have Military jets, who are exempt from ALL the rules, flying around at 400+ knots 500' above the ground without TCAS or ADS-B, and maybe not even an operating transponder.


Wow - so much BS in one paragraph, I'm impressed!. First, if you can't see an airliner coming towards you and avoid it, you should ground yourself (and not drive, either). Even F-16s are visible in plenty of time to avoid if you are actively looking. The real problem is the human eye and brain are not very good at the sustained task of visual lookout for ANYTHING. Second, since TCAS detects transponders, and ALL military aircraft are required to have their transponders ON when operating in joint civilian/military use airspace, TCAS is totally compatible with military jets (and many of the military transports have it also). Third, military aviation has even MORE restrictive rules than civilians, and military aviation is required to comply with civilian rules to the maximum possible when in joint use airspace. The only exception is speed, since some jets need to be above the 250 knot max airspeed limit down low - but that doesn't mean they are blasting around anywhere they want. VR and IR low level routes, along with MOA's, are other areas where some military flying will be fast and low - BUT THAT IS ALL TIGHTLY CONTROLLED AND SCHEDULED, AND YOU CAN FIND OUT WHERE IT IS HAPPENING BY CALLING THE LOCAL FSS! And finally, what military jet doesn't have an operating transponder? Again, ALL mil aircraft (including most UAVs) have transponders. Sure, it could fail inflight, but if it was broken before takeoff, that flight would not go until it was fixed - BECAUSE IT'S REQUIRED BY MILITARY RULES!

Before we have any more FAA mandates, we should insist that all Military jets be equipped with TCAS and ADS-B just like everyone else, and that ATC (both civilian and military) provide active separation services for all IFR aircraft under their control to avoid any transponder or ADS-B OUT equipped VFR aircraft that are visible on their radar screens.


More BS. Do you actually do ANY research before putting out this drivel?

Once everyone (including Military jets) are ADS-B OUT equipped, we will have an environment where low cost ADS-B IN systems can provide very accurate collision warnings to VFR pilots, so we can actively stay out of harms way.

Total, absolute BS. The time delay inherent with the ADS-B system, and the poor coverage at low altitude, makes it pretty useless as a collision avoidance system for military jets. Who, by the way, have a much better system (air-to-air radar, JTIDS, interrogators).

Will any military aircraft ever get ADS-B? Sure, airlifters and transports will probably get 1090ES so they can use international airspace. Fighters? probably not - unless it's a software upgrade to existing Mode-S transponders they now carry.

As usual, Mike, you are totally clueless.

Kirk
66

Kirk:

Maybe YOU should do a little more research before you start flaming people. Please explain to me how I'm suppose to visually see and a avoid a jet that is approaching me from behind at 250 knots?

You might also want to study up on how ADS-B works. All ADS-B OUT (both UAT and 1090ES) equipped aircraft transmit their position once every second. Any aircraft with an ADS-B IN receiver of the same flavor that is in the area will immediately receive this data directly without any time delays.

If an aircraft has a single frequency ADS-B IN receiver, and the conflicting aircraft is transmitting ADS-B OUT on a different frequency, an ADS-B ground station is required to translate the ADS-B OUT transmission to the other frequency. This introduces a 1-2 second delay into the process, which for most aircraft, which are trying to avoid each other by comfortable margins, is not significant. This delay obviously is a problem for gliders flying in close proximity in a gaggle.

A bigger problem is that if either aircraft is out of range of an ADS-B ground station (which can occur in remote areas at low elevations), the two ADS-B aircraft will not see each other. The simple solution to this is to install dual frequency ADS-B IN receivers. The current price delta between single and dual frequency receivers is so small ($200), that it doesn't make any sense to buy a single frequency ADS-B receiver, and I suspect that these units will disappear from the market in the not too distant future.

IMPORTANT NOTE: Keep in mind that you need to be ADS-B OUT equipped to reliably see any traffic data (both TIS-B and ADS-R) that is being transmitted by ADS-B ground stations.

On Wednesday, July 15, 2015 at 9:58:46 AM UTC-7, Mike Schumann wrote:


Walt:

You've hit the nail on the head. The FAA wants us to spend all this money, but then they don't use the data. Right now, under the FAA rules, ATC can watch an airliner heading straight for a transponder equipped VFR aircraft and not even give the airliner a traffic advisory, much less a minor course deviation to avoid a potential collision. Everybody is putting their trust in eyeballs and TCAS.

Eyeballs don't work when you are dealing with jet traffic. TCAS also is useless when you have Military jets, who are exempt from ALL the rules, flying around at 400+ knots 500' above the ground without TCAS or ADS-B, and maybe not even an operating transponder.

Before we have any more FAA mandates, we should insist that all Military jets be equipped with TCAS and ADS-B just like everyone else, and that ATC (both civilian and military) provide active separation services for all IFR aircraft under their control to avoid any transponder or ADS-B OUT equipped VFR aircraft that are visible on their radar screens.


Mike, I agree with you and on practically all of that. Kirk... I'm sorry... my eyeballs simply can't see (although my ears "heard one") a fighter jet crossing my path or coming up from behind.

ATC has all that data from transponders and in the future ADS-B. They could easily provide collision advisory servic if IT WERE A PRIORITY ... which it isn't (BTW... asking for radar VFR flight following isn't a practical solution). SSA in their argument against the transponder mandate should point this out. No transponders or ADS-B should be mandated for gliders until FAA provides a safety service for collision avoidance. I worked in the ARTCC (ZLA) as a meteorologist for 30yrs and looked over the shoulder of air traffic controllers. Sure, it's a burden to call collision advisories to non IFR traffic. But, with further automation... that's the point of Nextgen... a robotic voice COULD call the traffic on VHF sector frequencies or alarm the air traffic controller to broadcast these collision avoidance advisories.

BTW, Mike... I'm not on your side w.r.t equipping ADS-B on gliders. I'm definitely on the side of PowerFlarm with Daryl and Andy Blackburn...augmented by a Mode S (Trig) transponder. However, if FAA lowered the requirements for a certified GPS (lowered cost), and we could hook up our existing GPS's to the Trig... I'd be in favor of that.

Walt Rogers WX