They say this is because the red warning lights aren't visible in fog or low cloud.
BBC: London helicopter crash: What are the rules for pilots?
At the time of the crash there was low cloud, poor visibility and patches of freezing fog.
The inquest heard the aircraft took off at 19:00 GMT on 8 March 2011 in poor visibility and low cloud.
At that time, two men and two women were found stranded in low cloud, mist, and rain around midnight on Sunday.
BBC: NEWS | UK | Wales | North West Wales | Walker dies after mountain alert
Sometimes that is because of its latitude, but sometimes it is because it is covered by low cloud layers, which reflect sunlight.
Low cloud sweeps across the mountains followed by squally rain.
There was no moon, and under the low cloud cover a brisk unseasonable wind ruffled the old Norwegian maples that lined the street and dropped a fine rain of spring buds on my shoulders and in my hair.
Horrified onlookers watched as the helicopter hit the crane amid low cloud and fog near Vauxhall station, south of the river and not far from landmarks such as the London Eye and the Houses of Parliament, and came plunging to the ground.
By deeply optimizing for the Google TV platform to achieve low latency cloud gaming mode, Ubitus can enable OEMs to offer over-the-top (OTT) cloud gaming services to their customers at ease and timely.
ENGADGET: Google TV getting Ubitus support, promising 'console and MMO' quality gaming
Rather, it is offering a low-cost cloud service, with reliability that is not great but good enough for most users.
Caleta was drying up and emptying out until a coalition of Chilean environmental groups, Canadian researchers and international funding agencies decided to make use of the town's most valuable asset: Chamanchaca, a low-lying cloud that passes over the place almost every night.
In the low-risk category cloud computing and the continuing growth of mobile were the two most frequent predictions by pretty well all respondents.
That makes managed mobility powerful enough for most enterprises and certainly most startups and smaller firms, while delivering all of vaunted upsides of cloud: low cost, low pain.
FORBES: Managed Mobility Gets Even Better, Exposes Dithering IT Managers
Colin Le Ray said the system allowed planes to land in lower visibility by giving guidance to pilots, particularly when the cloud base was low.
Mr Le Ray said the system allowed planes to land in lower visibility by giving guidance to pilots, "particularly when the cloud base is low".
Data for each is transferred over Bluetooth Smart (low consumption) to Parrot Cloud, analysed by dedicated software and sent to a compatible Smartphone or tablet.
ENGADGET: Parrot's Flower Power monitors plant's environment, sends data to the cloud
The cloud is a low capital investment method for companies, such as social networks or games, to develop, deliver and scale without expensive upfront infrastructure investment.
FORBES: Why Mobile's Cloud-y Future Means Sunny Days For Amazon
The cloud provides a low-cost way for engineers, product developers and even marketing folks to experiment with new ideas and test their feasibility within a short timeframe so that they can quickly move forward with successful ones.
For years, the cloud was equated with low costs.
FORBES: The Key to Success in Cloud Computing? Good Plumbing
While there are other sites out there that will provide low-cost storage in the cloud, Skorny thinks Real has a couple of advantages in its close ties with the carriers (which should help with distribution) and its specific focus on making it easy to collect and then use content from any gadget you happen to use.
FORBES: RealNetworks Wants To Host Your Content. All Of Your Content.
Adopting a cloud service is a relatively low risk venture and further, models for virtually everything are available.
Passenger numbers at Cardiff Airport dropped by 200, 000 last year, with the airport blaming a cut in capacity by a low-cost airline and the ash cloud.
Today however, the rapid consumer adoption of mobile apps is what drives demand for cloud services, cloud platforms and cloud infrastructure, as the low capital investment and instant scalability enable speed to market and individual user adoption.
FORBES: Why Mobile's Cloud-y Future Means Sunny Days For Amazon
Other techniques aim to enhance marine cloud reflectivity by introducing sea salt aerosols in low clouds, mimic the effects of volcanic eruptions by injecting sulphate aerosols into the lower stratosphere, or place shields or deflectors in space to reduce the amount of incoming solar radiation.
One concern is that the shift to a cloud computing model will lead to an excess of low-level coders who do not have broad enough experience that enable them to build solutions comprised of many diverse parts.
"Google TV is an ideal platform for cloud gaming and we have tacked the obstacles to achieving low latency streaming game experience with multi gaming controller devices support on Google TV, " said Wesley Kuo, CEO of Ubitus.
ENGADGET: Google TV getting Ubitus support, promising 'console and MMO' quality gaming
We project that Salesforce.com will increase its market share in the cloud computing space over our forecast period, from a relatively low current market share base.
FORBES: Salesforce.com Needs Greater Share Of Cloud To Justify $140 Price Tag
The multimodal and multilingual speech engine runs on a cloud-based server to provide extremely high-quality recognition with low latency.
ENGADGET: QNX builds in-car speech framework with AT&T's Watson, knows our true intentions
They entered my office on a cloud of hope and expectation, stating that with interest rates so low, this was a perfect time.
Cloud provisioning, on the other hand, can be implemented rapidly and at low cost.
FORBES: Cloud Computing Now Makes It Easier (and Cheaper) to Innovate: Study
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