Getty ImagesAn F-16 readies for takeoff. Last week, Battleland bemoaned the increasing difficulty finding cost-per-flight-hour data for U.S. military aircraft. In a flash, longtime defense watcher – from a perch on Capitol Hill, as well as a stint at the Government Accountability Office – Winslow Wheeler piped up to say he recently sought, and got, such data from the Air Force comptroller’s office. He adds that he has tried to get similar data from the Navy, without luck. What’s up with that, Admiral Kirby? The Air Force provided Wheeler with cost-per-flight-hour for dozens of aircraft. Here’s a sample of what it costs to keep these Air Force aircraft airborne for one hour last year (the so-called “ownership” cost-per-flight-hour, which includes modifications): A-10C Warthog Attack Plane — $17,716 AC-130U Spooky Gunship — $45,986 B-1B Lancer Bomber — $57,807 B-2A Spirit Stealth Bomber — $169,313 B-52H Stratofortress Bomber — $69,708

C-130J Hercules Cargo Plane — $14,014 C-17 Globemaster Cargo Plane — $23,811hvac unit C-20B VIP Plane (Senior Pentagon Officials) — $32,212heating cooling wall units reviews C-32A VIP Plane (Vice President, Cabinet Officers) — $42,936rv a/c units for sale C-5B Galaxy Cargo Plane — $78,817 CV-22B Osprey Tilt-Rotor — $83,256 E-3B Sentry AWACS Radar Plane — $39,587 E-4B Flying Headquarters — $163,485 F-15C Eagle Fighter — $41,921 F-16C Viper Fighter — $22,514 F-22A Raptor Fighter — $68,362 HH-60G Pave Hawk Helicopter — $24,475 KC-10A Extender Tanker — $21,170 MC-130H Combat Talon II Special Operations Plane — $32,752 MQ-1B Predator Drone — $3,679 MQ-9A Reaper Drone — $4,762

RQ-4B Global Hawk Drone — $49,089 T-38C Talon Jet Trainer — $9,355 T-6A Texan II Turboprop Trainer — $2,235 U-2 Dragon Lady Spy Plane — $30,813 UH-1N Huey Helicopter — $13,634 VC-25A Air Force One — $161,591Window air conditioners are designed to cool one or multiple rooms that don't have access to adequate cooling. There are many things to consider when shopping for a window air conditioner, like size and maintenance. To learn more, here are 5 things to consider when shopping for a window AC: Cooling capacity should be your first consideration before buying a window AC. Cooling power is measured in British Thermal Units, or BTUs, per hour–the basic measure of thermal energy. For the best efficiency and effectiveness, stick with a unit that has a BTU level designed to fit your space. A window AC with too little BTU power will run continuously to try to cool a large space and, in the process, will eat up your energy budget. A window AC that's too large for your space won't cool and dehumidify your space evenly, leaving your room air susceptible to uncomfortable hot and cold pockets.

To find your ideal cooling capacity, calculate the size of the space you want cooled in square feet. Then use the chart below to find the right amount of BTUs. Area To Be Cooled (Sq. Ft.) Capacity Needed (BTUs Per Hour) For a more detailed estimate, take these factors into consideration, too: To view available window ACs for your space, check out our options for these spaces: Most window AC models are designed to fit inside standard double-hung windows. For step-by-step directions on how to install one through a window, check out our video and article on How to Install a Window AC. However, many models can also be installed inside a custom-created wall space with special mounting hardware. This is a useful alternative if your window's dimensions are too small or too large or if you don't have vertical sash windows. When completely installed–whether in a window or through a wall–the window air conditioner will sit level inside the opening, with the warm air exhaust system facing outside and the cooling system facing inside.

In addition, many window air conditioners feature a slide-out chassis and a rugged mounting sleeve that stabilize and secure the unit, while giving you easy access to it for maintenance. All window air conditioners come with detailed, easy-to-follow instructions for installation. Because window air conditioners are more powerful than other common household appliances, make sure your existing electrical system meets the needs of the unit's electrical requirements. Most room air conditioners operate on 115-, 125- or 220-volt circuits. ACs with cooling capacities below 15,000 BTUs usually run on standard residential (115- to 125-volt) circuits. Window ACs with cooling capacities above 15,000 BTUs usually run on 220-volt circuits. With these models, you may need to install special electrical wiring or seek out an electrician to assist you. Electrical requirements–including voltage, amps, and watts–will be listed in the specifications. In addition, the correct plug face type may be pictured or listed by its NEMA (National Electrical Manufacturers Association) classification.

In general, window air conditioners are a more economical choice than central air conditioners. They cost less to purchase and–if sized correctly–are cheaper to operate over the long-term. To gauge a unit's energy efficiency, look for two things in the product's specifications: Energy Star rating and/or EER number. Energy Star-rated room air conditioners use approximately 10 percent less energy than comparable models and save you money on operating costs. These efficient ACs also have features that give you better control over operation and energy output. These include programmable timers, digital thermostats, and multiple cooling speeds. Most states also offer rebates for customers who purchase an Energy Star model. An EER (or Energy Efficiency Ratio) measurement tells you how many BTUs the unit uses for each watt of power. Use this as a rule of thumb: the higher the EER, the more efficient the air conditioner. According to the U.S. Department of Energy, you should shop for a room air conditioner that has an EER of at least 10.0 for the best energy- and cost-savings.

Friedrich window air conditioners are known for both their high EERs and Energy Star-qualified operation. Window air conditioners require periodic maintenance to keep them in top condition. They can be vulnerable to outside dirt and debris, which can accumulate inside or on the back. In addition, dust and particles will build up on the air conditioner's air filter overtime. If left untreated, all of these things will eventually combine to reduce the effectiveness of your air conditioner. To ensure long-lasting operation, clean it thoroughly at least once per year. A window AC with a slide-out chassis make this convenient because all you have to do is slide the unit out to access it. Most air filters are washable with mild soap and water. For specific maintenance tips for your model, refer to your owner's manual. For protection from pests, some room ACs, like the Friedrich Kuhl Series, are equipped with mosquito traps that allow condensation to flow outside without letting insects inside.