Premium LED Lights: UK Zoom Stands Out

The $270 (ulp!) Surefire U2 is the worlds uber flashlight but the UK Zoom 4AA does the job at one- fifth the price on cheaper batteries.

by Frank Bowlin

Like a mirage, the perfect flashlight for flying seems to shimmer on the horizon, just out of reach. Our definition of perfection is a light that can be held and operated conveniently in one hand, has variable intensity-bright enough to ignite a match at 10 feet but dim enough to preserve night vision and with a uniform or adjustable beam that both floods and focuses. Batteries should last at least 12 hours and the entire package should easily withstand harsh elements and physical abuse. Is that too much to ask? In our review of inexpensive flashlights in the December 2005 issue of Aviation Consumer, we concluded that for under $20, you can expect a serviceable flashlight but little more. There are some good deals on inexpensive LED lights, but now we live in the age of the $300 flashlight so its fair to ask: Are they worth it?

For this follow-up review, were examining some of these high-tech flashlights with an eye toward lights suitable for exterior activities such as preflighting, fueling and repair and inspection. Although these products will do for in-cockpit use, many are simply too bright and will tank your night vision. Go with something smaller for cockpit use or choose one of these models carefully.

Many Choices
The market is increasingly swamped with so-called high-quality and expensive flashlights. High-dollar lights have become quite trendy. We borrowed a selection of products from manufacturers, most of whom sell direct through their Web sites. In addition, we also got a few lights from Sportys and, an e-tailer run by a pilot offering a bewildering selection of flashlights for any purpose. All of the flashlights in this review retail for more than $20-some a lot more.

Some of these lights are startlingly bright and provided good battery life. In our view, any light capable of more than three hours of continuous use is sufficient, particularly for preflight. Real-world intermittent use would produce much longer endurance. Most of the newer high-tech gas incandescent lights (Surefire and Streamlight, for instance) produce a bright, white beam as do all of the LED flashlights. A typical traditional flashlight produces a noticeably yellow light. While that might be bright, the whiter light seems brighter and renders better detail and color in its beam.

The trend in LED lights is polished reflectors and even some focusing lenses to improve the beam over the older LED designs that produce a diffuse, ill-focused beam with no ability to illuminate objects at a distance. Most of the lights produced a reasonably even beam with a bright center that dims toward the edges. While this is OK, we prefer more uniform beams with consistent intensity.

Some of the lights we tested offered multiple colors, with red being typically recommended for pilots. Red light has been shown to preserve night vision, but we simply dont like the way red washes out colors. In our view, proper color rendition is more important than maintaining the ultimate in night vision acuity. Instead, we prefer a dim white or blue-white light for cockpit use. The lights that offered colored filters were all too bright for cockpit use.

How We Tested
As in our previous report, we placed the flashlights on a fixed surface and illuminated a target at a measured distance, measuring the output with a light meter. The absolute value of the illumination is less important than how the lights compared.

For variable beam lights, we adjusted the beam to approximately the mid-point. We took light measurements at the center and various points outboard of the beam center. For variable intensity lights, we took all the measurements at full intensity and then just the center value at the other levels. All of the lights produced a much brighter center area within the 3-foot-wide beam.

We also positioned each flashlight at 10 feet from the target and measured the intensity at the center of the beam and at X and Y one-foot points and averaged the data. We crunched this data to produce subjective evaluations of beam quality: fair, good and excellent.

Finally, we turned all the lights on at their maximum intensity and measured their endurance with fresh batteries. Reports of 3+ or 3++ indicate only slight intensity decay over the test and a longer life. Since the duration numbers indicate time to reach half brightness, you can count on this time being the minimum life you could expect. In normal off-and-on use, the duration should be much longer. Also, depending on the battery type, there may (or may not) be significant life left past half brightness.

Tektite ( makes a wide variety of lights, some of which we reviewed in our previous report. This time we tested the Excursion LS4 and Trek 4. The Excursion has a good pattern, but its large and heavy with three D-cell batteries. The Trek 4, like the Lightwave Pro 2000 and 3000, has multiple LEDs with no separate reflector and the individual LEDs were discernable in the beam.Nice, but not exceptional.

We also tested the LPR2. This little gem is a high- intensity LED replacement for the bulb in the ubiquitous two D-cell Mag-Lite. It does improve the uniformity of the light, but its still subject to the poor beam quality of an otherwise solid flashlight.

Are pilots ready for $200 to $300 flashlights? Were not sure, but if so, Surefire ( is ready with some excellent products. Our favorite was the U2 Ultra because it offers six brightness levels of white light that range from dim enough for nighttime cockpit use to bright enough for a night preflight. The Aviator model has both white and red light, the former with an excellent beam but too bright for cockpit use.

These lights come with a heat warning for good reason. In our endurance test, both the U2 and Aviator were too hot to handle after less than 30 minutes. In flashlights that cost this much, we werent impressed with the switches, at least on the Aviator, a twist/push design thats awkward to use with one hand. The Ultra has a click on/off switch, which we thought was a better design.

This company has been around for some time in various incarnations. (See Their primary products havent changed much since we looked at them five years ago. Without a reflector behind the multiple LEDs, they simply dont provide a very focused beam. We were impressed, however, with the newer Infiniton C1. The unusual square beam produced a nice bright and uniform if very narrow beam.

Of the lights we tested from Streamlight ( a serious specialty manufacturer like Surefire, we found that the Task-Light 2L3W was the most suitable for pilots. It offers two useful brightness levels, but the dimmer of the two is still too bright for use in the cockpit. The large Twin-Task light offered by Sportys-another Streamlight product-is of an intriguing dual design, with a good quality Xenon flashlight that also has 10 LEDs. You can use five or all 10. With all 10 LEDs, the light was comparable to the Xenon bulb, but with a better pattern. Were not sure theres any advantage in offering both. We found that the five LED setting was still too bright for the cockpit.

Streamlight also offers the Key-Mate, an LED powered by four button batteries small enough to fit on your keychain. Its offered in white, blue, red and green LEDs and was surprisingly bright for its size, but inadequate for a preflight inspection.

Ready to program your $245 flashlight? HDS Systems ( offers amazing little lights that provide programmable brightness levels and flashing patterns, like an SOS. Were not sure how practical it is to expect a user to press the button 10 times, then press and hold for half a second, then, well, you get the idea. (To be fair, however, it isnt that difficult to select different intensities and the dim setting is excellent for use in the cockpit.) The light output is excellent and uniform and had the brightest light for its size by a large margin. We were also impressed by the endurance of this flashlight, given its high intensity and small size.Although nicely made, $245 for the Ultimate and $120 for the Basic EDC models is on the pricey side.

Underwater Kinetics
As the name implies, UK ( specializes in lights for divers but these clearly have other applications.We tested the 4C model in 1995 and again here. It arranges the four C cells in two rows, making for a comfortable fit in your hand. Admittedly, that many batteries give it an advantage, but its still one of the brightest lights in the bunch. The beam, however, was irregular with bright and dim spots. Not our first pick, by any means. UK also sent us a small 2L light that was bright and amazingly long lived. Unfortunately, its irregular, uneven beam kept this from being a favorite.

The surprise came from UKs 4AA Zoom LED light, an LED version of the Xenon light that rated highly in our December review. Like the bulkier 4C, the four AA batteries are packaged in two parallel rows, making this a compact light. It has a focusing lens and an effective reflector. The beam width is somewhat adjustable with the light output remaining even.Brightness was excellent as was beam size. It offers a lower brightness setting thats still too bright for cockpit use, however.

Also Rans
The compact Coast LED Lenser from Sportys was an average performer with adequate brightness, broad beam and good endurance, but the red LED was too bright for the cockpit. The Garrity K009G from had good beam uniformity from a focusing lens and excellent battery life, but it was a bit dim. The Smith & Wesson 3x Galaxy from suffered the same dual light source schizophrenia as the Streamlight Twin-Task, not offering remarkable qualities in any mode.

We tried two so-called shake or Faraday lights that use a built-in generator that works by shaking the light. This idea has potential and the samples here offered good beam spread and uniformity. Unfortunately, theyre just not bright enough and only lasted a few minutes, requiring more shaking than youd probably want to do. Nice idea, but just buy an extra battery powered light instead.

Our Picks
If money were no object-yeah, that sounds bizarre for a flashlight purchase-wed pick either the EDC Ultimate 60 XR or the Surefire U2 Ultra. The EDC is smaller and cooler-running than the Surefire and offers excellent brightness at a smaller size. The beam of the Surefire was a bit too broad for our preference but these are extraordinarily well-made flashlights. If we owned one, we would be terrified of losing it.

In the real world of fiscal compromise, the UK 4AA Zoom LED is by far the top value. In this arena, its $50 price tag is moderate for outstanding performance and we think it provides the best overall value. Although not the brightest, its one-fifth the cost of the high-dollar flashlights and offers comparable performance, plus, the batteries are cheaper and available at the corner convenience store. The lithium batteries used in the high-dollar lights are both expensive and not always easy to find.

Also With This Article
“Product Specs, Comments, and Prices”
“The Smackless Flashlight”

-Frank Bowlin is a freelance author and airline pilot.