Problems with Jungle Jet Radar

TWA Dude

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To all you Embraer Jet jockeys:

An EMB captain/friend of mine just called me to ask if my 717/MD80 radar could paint t-storm echoes when at cruising altitudes FL350 and above. I said of course it did. He said his radar wouldn't paint any echoes whatsoever no matter how he tilted, gained, or intensitied the knobs even when he had a visual on nearby convective activity. He also said he had to use a tilt of +1degree just to get rid of the ground clutter. At 350 you should be at least -5degrees before getting ground clutter. He was very disturbed as it wasn't just one airplane but every Jungle Jet was the same. Of course management couldn't care less. I told him as a start he should fill out NASA forms and encourage others to do the same.

So, anyone else notice problems with the Jungle Jet radars?
 

Prop Trash

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I've heard the shape of the radome is one reason why the radar is defficient. I was told that the EMB-145 gets struck by lightning more than any other type of aircraft. It's probably because the radar causes pilots to fly through weather they shouldn't be in.
 

Saluki Dawg

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The radar on the Jungle Jet SUCKS!!! and is going to get someone really hurt someday. It's pretty bad and embarrassing when I have to ask the controller to find out from the aircraft ahead of me if I'm heading into a Convective Cell because my radar won't accurately depict Wx. It's not as bad during day ops because you can usually see what you are trying to avoid flying into. Night ops is a whole other story, and you will usually penetrate something you wish you hadn't with that radar. That's been my experience with it, but other's may have better luck with it than I do.
 

EagleRJ

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The problem isn't the radome, it's the size of the radar dish. Remember that radar sensitivity increases with dish diameter (narrower beam). The ERJ's pointy schnozz can only fit a 12" dish, compared with a 16" or larger dish on the CRJ and the larger turboprops. I've heard that Embraer is looking at installing a bigger dish, although there's not much room for it to swing back and forth in that radome.
 

surplus1

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Is the nose section of the ERJ very different from the E-120? The 120 radar used to work fine for me.
 

AWACoff

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Surplus,
I had my share of problems with the E120. Almost all were due to moisture penetration of the radome. The E120 isn't cruising above FL300 very often...I imagine that has something to do with our radar in the E120 working "better". It's not like there's ever thunderstorms in the jungle anyways...who needs radar.
 

eaglefly

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After 1400 hours in the "junk jet" (10,000+ total) I agree the radar in the A/C is hazardous. It isn't too bad one the ground prior to departure but once airborne especially at higher altitudes it is shaky to downright useless.

There are several factors at work. Yes, its dish is smaller than an ATR or SF3. It also has moisture problems because of penetration within the radome as well as into the "abrasion Boot" on the exterior tip. This aircraft takes more lighting strikes than any other transport aircraft because of its extreamly poor ability to dissipate static. You don't need to penetrate a CB to take one, just fly through adversly charged air. P-static frequently renders the comm radios almost useless and since static electricity concentrates at the sharp ends of the A/C, the Radar is affected by this as well. Combine some or all these factors and you have to operate as though you have no radar at all.

I cant wait to transition to something safer.
 

Ted Striker

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I remember the E-120 radar working well until, like AWACoff said, it got moisture in it. Then it was worthless. Does the jungle jet have the exact setup?
 

surplus1

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Sounds pretty alarming. I hope you all are filing NASA reports and SDRs. If this radar can lure you into dangerous weather something should be done about it NOW.

RE the E-120, although I flew it for about 5 years I never personally experienced moisture penetration of the radome. I know the domes were replaced/repaired more frequently than other types I've flown (due to abrasion -- we wound up adding a special exterior cover/tip) but I never had a problem with the radar (other that the rare deferral).

Are the nose cones identical on both aircraft or are the ERJs different?

Eaglefly, thanks for the info on static dissipation. Interesting, to say the least. From your description I'm not sorry I don't fly that aircraft. Personally I like to work at keeping the airplane dry in the vicinity of convective Wx.
 
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fr8trash

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I have been flying checks and urine samples in my 310 and just wish there was a radar in my airplane. The bruises on my hips from going through storms last week in the STL area hurt today.
 

tdvalve

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'The ERJ's pointy schnozz can only fit a 12" dish, compared with a 16" or larger dish on the CRJ and the larger turboprops. '

12" dish seems to work fine in the Lears and Citations.
 

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Shem Malmquist
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The smaller dish works ok for smaller ranges. Even with our 30" dish the resolution beyond 80 miles isn't very good (and that applies to all 30" dish radars, not just in the airplane I fly, which is better than most of the others I've flown in this regard). While I can start planning for wx avoidance 100 miles or more out with fair accuracy, the small dish will have to wait until 30 miles or less to get the same resolution.
 

tdvalve

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No doubt the bigger the better on dish sizes. I seldom try to paint beyond 50 miles with a 12 incher but occasionally look out to 100 miles. While the resolution is not that great, useful info can be obtained beyond 50 miles. Can't imagine why the EMB won't paint cells when above 350.
 

surplus1

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Tdv and profile,

We're on the same page with this one. I don't understand the relevance of the altitude and there are lots's of 12" dishes that do just fine.

I'm wondering now what if anything the avionics dept. is doing to fine tune these radars and maintain the domes.

There's something more than dish size and FL in this equation.
 

TWA Dude

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To All:

Thanks for the reports. I'm passing on the info to my friend that he's not the only one experiencing problems.

While dish size is important it can't explain why close-by cells aren't showing up while flying at high altitudes. Keem them NASA reports comin'.
 

eaglefly

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Lears, citations and EMB-120's don't take lightning strikes like the 135/140/145 series. I firmly believe the BIGGEST culprit involving this A/C's poor radar performance is that big ball of static electricity at the nose.
 

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Shem Malmquist
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Sounds to me like the radome is the most probable culprit. Would be interesting to learn more about this. If someone here who has experienced this could send me some detailed info in a private message, the exact model number of aircraft, type of radar installed, altitudes, distance, location of occurences, I think I can get it to the right folks to look into the situation. Are you an ALPA carrier? If so, include that info as well. There may be a way to fix this.
 
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