It was a meeting of the minds!
It was hangar flying at its best!
It was before COVID-19 shut us down, and the topic stuck with me like a bad cold…
The upstairs room in the terminal building held a dozen or more local pilots, all watching a video presentation prepared for the monthly IMC/VMC Club meeting. As it played out, the pilot in the scenario had lost functionality of the airspeed indicator prior to entering the pattern.
Like all other IMC/VMC scenarios discussed, we were only given knowledge of a situation as another pilot experienced it… right up to the point of, “What would YOU do?” We never discover how things play out for the pilot, or even what caused the problem in the first place.
At the end of the video, the low buzz of discreet discussions could be heard throughout the room as pilots sitting next to one another worked out the situation at hand.
After a quick recap, the presenter
asked for notions as to what happened and why. On this particular night, the discussion revolved around whether or not you could land without the airspeed indicator when flying IMC (instrument meteorological conditions).
Thinking of all the gages lining the dash of our Piper Archer ll that would help determine airspeed, I couldn’t think of a single alternative. As the old aviation mantra goes, “Airspeed is life,” and knowing how much I rely on the airspeed indicator during every landing sequence, I’d surely suffer a panic attack if this instrument had suddenly failed.
Recollecting how many times I adjust the pitch and power in order to get the airspeed needle exactly where I want it on final, I agreed with the other pilots in the room that learning the sight picture during a VMC (visual meteorological conditions) landing would be a good idea. Associating the sight picture with the attitude indicator would also be helpful in successfully landing without the ASI.
In a Pilots of America forum, this same question is addressed, but the pilot in this scenario had also discovered after landing that a plastic bag had gotten snagged on the pitot tube during flight.
Aside from having an intestinal emergency (as one pilot mentions) and attempting to melt off a possible clog by flipping on the pitot heat, every pilot in the forum agreed that finding the perfect pitch and power combination for the airplane would save your bacon.
Doc Green offers further advice for practicing this emergency technique. In his article, Flying without an ASI, he mentions four main practice points:
First, try the pitot heat.
Maybe a bug is clogging your beloved ASI. Flip on the heat and see if you can scorch the crusty carcass loose! If this fixes the ASI, then all is well for your landing.
Second, fly by pitch attitude.
Fly to a safe altitude, lower the engine RPMs and adjust the pitch attitude to hold the airspeed as you would on final approach. Memorize where the nose is in relation to the horizon and practice until you can repeat the nose attitude without using the sight picture or your ASI.
Third, memorize the pitch of a stall.
Do you know your airplane’s stall speed, and where the nose is in relation to the horizon just before stalling? Practice how far you can pitch the plane safely before stalling until you can do it from memory. This way you’ll be sure not to pull her nose up too high while landing.
Fourth, use the VSI (vertical speed indicator) during descent - if you have one.
Figuring a descent rate of 500 feet per minute will keep your speed on target for a safe landing. If you don’t have a VSI, Doc Green recommends adjusting your pitch attitude (step 2) for the correct landing speed, then lowering the nose a bit. The idea is it’s better to carry a little more speed than drop out of the sky, but not so much speed that you blow off the end of the runway.
If you haven’t had time to practice and you find yourself in this ASI crap-out situation, practice finding your safe pitch attitude before entering the pattern (depending on fuel reserves).
In the end, even after you successfully land without the aid of the ASI, don’t forget that it’s a required instrument and you should never fly knowing it’s not working properly.
Have you ever landed without your ASI? What instruments did you use to help aid in your success?
Thanks for reading!
For more information on a dealing with a broken airspeed indicator, check out these links:
Bergqvist, Pia, September 27, 2011, Airspeed Indicator Breakdown: How to Fly, https://www.flyingmag.com/technique/tip-week/fly-without-airspeed/
Cutler, Colin, July 2, 2015, How Does Your Airspeed Indicator Work, And What Happens When It Fails?, https://www.boldmethod.com/learn-to-fly/aircraft-systems/how-does-an-airspeed-indicator-work/
FAA, Flight Instruments, https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/10_phak_ch8.pdf
Pilot Workshops, Moran, Wally, Feeling your airspeed, https://pilotworkshop.com/tips/pilot_feeling_airspeed/
Bertorelli, Paul, November 28, 2018, Who’s Afraid Of A Dead ASI?, https://www.avweb.com/flight-safety/technique/whos-afraid-of-a-dead-asi/
Doc Green, Flying without an ASI, http://www.challengers101.com/NoASI.html