Mountains Archives - Page 2 of 3

Scary video encounter with density altitude

Density altitude can be an invisible danger for high-altitude mountain flyers on hot summer days. Moreover, combine the perils of density altitude with adverse or misjudged runway conditions plus shifting winds and you can easily and quickly have a disaster on your hands.

And there is no better evidence of this than some of the footage in this recent video interview of Chris Palmer by Jason Schappert. As you will see in the video, Chris explains to Jason how “something happened with the wind that totally took our margins away.” However, both luck and “pilot instinct” allowed Chris to pull out of this particularly dangerous situation where he literally had to fly through a gap between some very tall trees.

Among the lessons mentioned by Chris included the need to really KNOW you aircraft (a Bonanza in his case) as an aircraft’s actual performance may not meet your expectations should you find yourself in the same situation as he did.

All about density altitude

The July/August issue of FAA Safety Briefing featured an interesting article (“Climbing into Thin Air”) discussing density altitude – an invisible danger for high-altitude mountain flyers on hot summer days. The FAA article began by providing this description of density altitude:

There is a thief among us! Without warning, it can sneak into your airplane and rob you of precious lift, thrust, and power. And, if you’re not careful, it can quickly put you in a deadly spot during your next flight.
The culprit here is not something particularly obvious, nor is it something pilots who routinely fly at or near sea level are used to dealing with.

The article then related the story of a fatal accident that recently occurred in Arizona where a pilot failed to attain and maintain an adequate airspeed during takeoff in high density-altitude conditions. This resulted in an aerodynamic stall.

The article continued by noting that when density altitude is high as a result of temperatures that are above standard at a given altitude, the air is less dense than normal. Hence, an aircraft will perform as if it were flying at a higher altitude with decreased climb performance and acceleration ability. This can be a big problem if you are flying on a hot and humid summer day and if you are operating from a short runway that has a few tall pine trees at the end of it.

However, a hot day can have an affect on aircraft performance at any altitude. Hence, the article quoted one flying expert who suggested that pilots need to become familiar with the weight-and-balance along with the performance and limitations sections of a pilot’s operating handbook (POH) or airplane flight manual. In addition, avoiding takeoffs and landings at midday when temperatures are usually at their highest and instead taking advantage of cooler mornings or evenings will also help to avoid performance surprises.

In other words and if you plan on doing any summer flying, be aware that humidity and temperatures can impact your aircraft’s performance and be sure to plan accordingly.

Tips for mountain flying

Mountain flying can be particularly dangerous if you are not prepared for it. Moreover, pilots often have a lack of understanding when it comes to flying in mountainous areas.

Hence, a recent post written by Jason Schappert for the Let’s Go Flying blog about crossing mountains plus a podcast he did for his MzeroA.com blog are well worth noting. In his post for Let’s Go Flying, Jason mentioned three key tips for mountain flying:

Know Your Route Inside and Out
Always Have A Way Out
Timing is Key

However, his most important point was that mountain flying tends to be an early morning event because the temperatures are lower allowing for lower density altitude. Moreover, the winds would not have pick upped yet and this reduces the risk of mountain waves and extreme turbulence.

Meanwhile and in the podcast, Jason explained the following important mountain flying concepts:

How to approach a mountain pass
How to always leave yourself a way out
How mountain waves effect you as a pilot

Jason’s post also includes the full transcript of the podcast which is also well worth reading through along with some pictures he has taken of flying through mountains.

Gliding in the Alps in HD video

This is probably the most beautiful bit of aviation filming I have ever seen. It’s just gorgeous. It’s mostly film taken from a glider in the mountains around Sion in Switzerland at 10,000-21,000 feet. If you’ve never flown before, this film will explain why we do it. It’s worth clicking on the ‘full screen’ button just to see it in all its HD glory.

High altitude flying safety video

Flying over mountainous terrain or in high altitude conditions is different from flying close to sea level and hence, pilots need to be aware that they will encounter a whole different set of conditions. Moreover, the fact that even experienced pilots and adventurers like Steve Fossett can be downed by downdrafts over the Sierra Nevada mountains should be a lesson for less experienced pilots or those not accustomed to flying in high altitude conditions.

Hence, Paul Tocknell has recently posted on AskaCFI.com a dated but still relevant flying film from the FAA entitled “Density Altitude.” In the film, a young couple takes a flight from New Orleans (sea level or below) to Denver and eventually to Lake Tahoe in the high Sierras after crossing the Rockies. In the film, the couple learns the hard way that high altitude and temperature will impact the performance of a light aircraft (Note that Steve Fossett was flying a single-engine, two-seater Bellanca 8KCAB-180, also known as the "Super Decathlon"). The film runs for about half an hour and although the participants in the film may not have won an academy award for their acting performance, the film still contains important safety information that pilots who will be flying in high altitude conditions need to be aware.

Mountain flying tips

Flying over mountains in a small plane can be tricky, especially if those mountains are on the scale of the Rocky Mountains (or for that matter, the Alps or the Pyrenees in Europe). Hence, Brian has posted a very detailed post about mountain flying (specifically the Rocky Mountains in a small plane such as the Cessna 182) on Brian’s Flying Blog.

Brian begins by suggesting that you first fly near a mountainous area and get some specialized instructions by local instructors who are experts in flying over mountainous terrain. In addition, he also posts some helpful links to mountain flying books or resources on the internet with Mountain Flying LLC by far being the most useful resource available (sadly however, the man behind the website and a number of books about mountain flying, Sparky Imeson, recently passed away in plane crash). Brian then posts a number of tips that he has picked up from these sites and has them conveniently posted under topics that include landings, takeoffs, climbouts and crossing ridges.

Hence, the post is a must read by any pilot who has plans for flying over a mountainous area in the near future.