Dodgy weather radar in Metro aircraft

[Centaurus]

Over the years I have talked to many current and former Metro pilots. A familiar subject that comes up in conversations about flying the Metro is the surprising number of adverse comments on the poor reputation of the weather radar systems installed in these aircraft.

Most complaints are about failure of the radar to pick up obviously significant thunderstorms yet are ground tested serviceable when verbally reported to maintenance. Note my use of "verbal reports to maintenance" rather than written reports. I think this point is significant. After all, a written report on a defective weather radar would be the cause of grounding an Airbus or Boeing - so why not a Metro?

Forgive the generalisation, but the impression I get is that Metro pilots in general are reluctant to enter details of the defective radar in the maintenance release for various reasons. The most common reason being "it is a waste of time because it makes no difference." This suggests a sense of apathy yet an inadvertent penetration of a thunderstorm at the altitudes that Metro aircraft fly is no laughing matter even to the most experienced IFR pilot.

Has any Pprune reader struck similar problems when using Metro radar, past or present? If so, this suggests an airworthiness problem worthy of the attention by the Regulator

[Roj approved]

Metro radars are generally pretty ****, most operators of Metros are of the "GA" style of operation. Therefore, all the trappings of "GA" operations, ie: non reporting of defects, no money spent on aircraft, "ground tested OK" etc.

Eyeball Mark 1, lots of fuel for off track diversions, general smarts to avoid the weather, and an updated resume to move to an operator of higher standard will work in your favour.

In saying that, I really enjoyed my time on the Death Pencil, but I only ever did freight.

[Judd]

Therefore, all the trappings of "GA" operations, ie: non reporting of defects, no money spent on aircraft, "ground tested OK" etc.

Unless the radar defect is accurately described by the pilot in the maintenance document, then the electronics people don't have much to go on in their diagnosis of the defect - if indeed there is a defect and not just the defective knowledge of the pilot on the limitations inherent with the operation of radar. For example, radar attenuation in heavy rain.

Pilots also need to read the POH for the radar in their aircraft. If the operator doesn't supply a radar POH, then search the internet - there is no shortage of excellent technical information for pilots on that subject.

Poor radome quality is a common cause of inefficient radar signals. Pin hole size damage, leaking seals and even incorrect paint repairs all serve to attenuate the radar signal. Typically, water gets into the honeycomb surface of the radome and then freezes at low temperatures common at high altitude. Radar cannot penetrate the thin ice layer on the inside of the radome and a thunderstorm cannot be "seen" until the aircraft is so close that a penetration may occur. On the ground the ice disappears and 'ground tested - serviceable` report is the usual result.

[Metro man]

The Metro was getting on a bit 10 years ago when I was flying them and probably wouldn't be worth a significant investment in upgrading to modern standards. We had a few variations in the avionics and instrumentation ranging from basic trainer panel with mono chrome radar up to flight director and colour radar.

Post #2 has described things pretty accurately, a few big bills can easily tip a GA operator on thin margins into the red. A mate wrote up a snag which resulted in a $20 000 bill, luckily he was with the RFDS !

[Band a Lot]

What was the non RFDS price?

[Sunfish]

metros allegedly also use other dodgy equipment

[get_over_it]

It's safe to say the weather radars in Metros and similar vintage radars shouldn't be relied on if you can't see outside or want to see beyond the crap in front of you.


As Judd said, water leaks and paint repairs are typically the culprit. These things only get worse with age.


A C&T captain taught me to always do my homework on where we were going and what might happen, with storms in particular, from multiple sources. The online weather radars these days are gold - one wonders why Metro guys can't access them from the cockpit.

[Band a Lot]

The online weather radars these days are gold - one wonders why Metro guys can't access them from the cockpit.

I heard they kill people as distance from radar = height that weather is displayed on such platforms.

[Metro man]

Even on the Airbus the radar isn't that great, I've been in dead smooth conditions with the display showing red and moderate turbulence with it showing green.

The skill in avoidance is knowing what to expect from looking outside, a red return from a CB at FL350 is something to avoid whereas extensive red from nimbostratus at low level isn't much cause for concern. Towering cumulus at higher levels are more of a problem because there is very little water content to reflect back but considerable air currents. These clouds typically place themselves exactly on the airways and aren't seen until you are almost inside.

Weather patterns and formations are often a better guide when looking at the radar than the actual colours. At jet speeds avoiding action needs to be taken early and often a previously decided course of action needs to be revised due to rapid changes in a system.

[Roj approved]

its not much better on Boeings latest product:rolleyes:

[das Uber Soldat]

Hah, metro weather radars. Whilst I miss the Metro I don't miss the useless radar in them. You can write it up but its a pointless exercise. I remember a concerted pilot effort to write up the linear deviation switches, the ignition lights and the lack of audible A/P disconnect alarm (single pilot ops). End result? Not a thing changed for years.

I went into the office of the safety manager and he was genuinely at a loss as to why I was cranky. After all, we had put the safety reports in. Therefore the system worked! That nothing had changed was of little consequence, he'd done his job by running the SMS. The decision to actually do anything was out of his hands you see, lots of signatures required etc etc. Was like pounding my head against a wall.

I put in a safety report about the safety reporting system after that. They just deleted it.

Good times.

[cattletruck]

Does sound like the primary purpose of the Metro weather radar is to counter a rear CofG.