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Tips to Help Streamline IFR Training

September 21, 2012/in Tips and technique/by studentpltnews

When stressed learning to fly approaches, it is very easy to get behind the airplane. During my IFR training, it was not uncommon for my instructor to ask me, “What is the next thing to do?” And sometimes it was difficult, if not impossible, to answer! In any stressful situation, the human mind easily can […]

Performance in the Real World – Part 2

September 3, 2012/in Tips and technique/by studentpltnews

Takeoff performance calculations start with a chart from the airplane’s POH but there may be more to the story. We’ll take a look at one of these charts along with the conditions and notes on the chart that many pilots overlook. We’ll also address what to do when the runway just doesn’t fit the mold defined by the chart.

Tips to Help Streamline IFR Training

September 21, 2012/in Tips and technique/by studentpltnews

Performance in the Real World – Part 2

September 3, 2012/in Tips and technique/by studentpltnews

Full Sized Blog Element (Big Preview Pic)

Tips to Help Streamline IFR Training

September 21, 2012/in Tips and technique/by studentpltnews

Staying ahead of the airplane is much easier if the IFR pilot realizes that 1) there is a generic basic flow to every IFR flight and 2) when the items in the basic flow are memorized, mistakes are minimized. Furthermore, if the IFR pilot knows the items that are needed to fly a specific type of approach (e.g. GPS, VOR, or ILS), stress and mistakes are further minimized. In my experience teaching IFR flying, requiring students to memorize these items results in students having less difficulty learning approaches.

BASIC FLOW OF ALL IFR FLIGHTS

Each IFR flight terminating in an approach has the same basic elements, as outlined below.

1. Get started. Obtain clearance and follow ATC instructions for climbing to a specific altitude and heading. Upon reaching desired altitude, level off and complete the cruise checklist.

2. Run through the approach briefing. Set up for the approach via an approach briefing. Although there may be other useful checklists, my choice has been the WISP and ICE ATM checklists (see below). Each checklist emphasizes different items and, therefore, it may be helpful to run through both checklists to double check that the set up for the approach has been thought through completely and properly.

– ICEATM:

I – Enter the Localizer or VOR frequencies and identify them via the Morse code or enter the approach into the GPS.

C – Set the inbound course using the OBS knob on the VOR or HSI.

E – State method of approach entry (full or vectored) and make sure it is properly entered in the GPS if flying a GPS approach. If a full approach, make sure to run through the entire procedure (holding pattern, DME arc, etc).

A – Run through the altitudes used in the approach, i.e. 1) initial altitude at start of approach, 2) step down altitudes if present, and 3) MDA or DA altitudes.

T – Is the timer needed – is it a timed approach?

M – Run through the missed approach instructions.

This list is followed by the nice-to-dos, such as: listen to the weather, make sure the marker beacon is on if needed, and make sure the CDI of the VOR or HSI is slaved appropriately to either the VOR or the GPS.

WISP:

W – Obtain the weather.

I – Make sure your flight instruments are set correctly (e.g. set barometric pressure, and CDI correctly).

S – Go through the avionics stack from top to bottom and make sure everything is set correctly (e.g. slave the CDI to the GPS or VOR, activate the marker beacon, tune in radio frequencies, tune in and identify VOR frequencies, or load the GPS approach into the GPS).

P – Run through the approach procedure, including the missed approach directions.

3. Expect missed approach instructions. Expect ATC to deliver these instructions prior to joining the approach course. Be ready to copy them down.

4. Join approach course. Anticipate joining the initial or final approach course. Instrument scan elements that need particular attention include, 1) distance to IAF or FAF shown on the GPS, and 2) CDI movement. Vocalizing the distance to the IAF or FAF aloud each time the eyes look at the GPS during the instrument scan is very helpful in maintaining focus on the IAF or FAF. This minimizes flying past these fixes without realizing it. If flying a full approach, once the IAF has been reached, running through the five Ts is helpful (as it is when passing any waypoint) (see below for the five Ts). For this portion of the approach, the clock becomes a necessary part of the instrument scan. When the time is vocalized aloud each time the eyes look at the clock during the instrument scan, the pilot remains focused on the endpoint of the leg being flown. Again, the mistake of flying past the waypoint and not realizing it is minimized using this technique.

Time – start the clock (or note the time)

Turn – turn to the new heading

Twist – turn the OBS to desired course

Throttle – change power setting if needed

Talk – talk to ATC if necessary

5. Run through the SADS checklist 2 miles prior to reaching the FAF. Two miles prior to reaching the FAF, it is prudent to run through this checklist to ensure a smooth transition to the approach course.

S – Slow down to appropriate speed (e.g. 90 kts for Cessna 172). Incorporate looking at the distance to the FAF into the instrument scan and say the distance aloud each time the eyes look at the GPS during the instrument scan. Again, this keeps the focus on the FAF, making it difficult to fly past it without starting the descent on time.

A – Altitude check. Is the current altitude the altitude allowed in this segment of the approach (i.e. is a descent allowed to a lower altitude?) and reread the DA or MDA.

D – Descent checklist. Perform the descent checklist.

S – Set-up for descent. When arriving at either 1) the FAF for a nonprecision approach (VOR, nonprecision GPS, localizer, or NDB approach), 2) the glideslope of a precision ILS approach, or 3) the glide path for an APV approach, lower the flaps, decrease the power and pitch down to attain the proper descent rate for the approach leg. The pilot should know the approximate pitch and power settings that will result in the airspeed/descent rate needed for a precision and nonprecision approach (e.g. in a Cessna 172 put in 10 degrees of flaps, pull the power back to about 1600 RPMs and pitch down about 4 degrees to maintain 90 kts while descending in a precision approach).

6. Descend to MDA or DA. The instrument scan now should include calling out altitudes as the descent is made down to the MDA of a nonprecision approach or a DA of a precision approach. If the airport environment is not detected at the DA, a missed approach should be initiated. If flying a nonprecision approach, once the MDA has been reached, 1) the distance to the MAP or 2) the clock (if a timed approach) should be included in the scan. As stated previously, it is helpful to say aloud the distance or the time each time the pilot looks at the GPS or clock so that the pilot does not fly past the MAP.

Staying ahead of the airplane is key to reducing stress and successfully completing an IFR approach to a runway environment. Use of the above techniques aid in minimizing errors in flying approaches and similar techniques can be useful in flying holds, as well.

Wishing you safe and enjoyable IFR flights!

Performance in the Real World – Part 2

September 3, 2012/in Tips and technique/by studentpltnews

More Than Just the Calculations

In my last post, I discussed Pressure and Density Altitude calculations and their contribution to the total performance equation. In this post, I’ll cover some of the other values in the takeoff equation that we don’t always keep in mind.

When calculating performance for our airplane, we use the charts found in the Pilot’s Operating Handbook (POH) for our aircraft. These charts generally account for density altitude and include conditions and notes to address other factors. When was the last time that you took a close look at the conditions and notes associated with the chart? They are important and are there for a reason.

As an example, the “Short Field Takeoff Distance at 2550 Pounds” table for the Cessna 172S lists the following conditions:

Flaps 10°
Full Throttle Prior to Brake Release
Paved, level, dry runway
Zero Wind
Lift Off: 51 KIAS
Speed at 50 Ft: 56 KIAS

It also includes the following notes:

Short field technique as specified in Section 4.
Prior to takeoff from fields above 3000 feet elevation, the mixture should be leaned to give maximum RPM in a full throttle, static runup.
Decrease distances 10% for each 9 knots headwind. For operation with tail winds up to 10 knots, increase distances by 10% for each 2 knots.
For operation on dry, grass runway, increase distances by 15% of the “ground roll” figure.

Many of these items are related to technique and aircraft configuration and are easy to comply with. Some can be tougher.

Take the “Paved, level, dry runway” condition. This seems simple enough but have you checked the grade on the runway at your home airport? What about the runway where you are planning to land and will have to later takeoff? Do you know where to find this information? Do you know how it will affect your takeoff distances when you find this information?

Runway slope information is published by the FAA in the Airport/Facility Directory. The information can also be found on the Airport Diagram or Airport Sketch for the airport in the Terminal Procedures Publication (approach plates). Many commercial sources, GPS databases, and pilot apps also include the information.

Looking at the Clermont County / Sporty’s Airport, we find a slope of 0.9% uphill on runway 22 and the same slope downhill on runway 4. This equates to about 32′ of elevation change from one end to the other of the 3566′ runway. The grade is not a consistent slope of 0.9% but there isn’t information readily available that tells us what the slope is at different points along the runway so we’ll stick with the 0.9%.

The chart in the POH doesn’t provide any indication as to what we should do when the runway is not “level.”

For help in addressing this adjustment, I would look to an expert in flying on “non-level” runways. The late Sparky Imeson, author of the Mountain Flying Bible Revised suggests the following rule of thumb with regard to gradient. For a 1% upslope, which is approximately runway 22’s slope, increase the takeoff distance by 7.5%. While not specified on the Imeson family’s website, this should be 7.5% of the ground roll. If a 2% upslope, use a 14% increase; 4% upslope, 25.5% increase; and 6% upslope, 39.5% increase.

Another aspect of the notes which has no resolution in the POH is departing from a wet or otherwise contaminated runway.

A wet runway will change the friction between the tires and the surface. While this may decrease friction, I wouldn’t expect it to shorten the takeoff roll.

Standing water will increase the takeoff roll. This is due to “displacement and impingement drag” as the spray from the tires is displaced and strikes the aircraft. The FAA’s AC 91-6A regarding Water, Snow, and Slush on the Runway hasn’t been updated in over 30 years. At that time there was no clear engineering data on how much water or slush on the runway affected the takeoff roll.

You should not attempt a takeoff when standing water or slush on the runway is more than one half an inch deep.

Imeson’s website has some rules of thumb regarding surface contamination as well.

Cessna recommends increasing the ground roll figure by 15% when taking off from a dry, grass runway. This guidance may be incomplete as it does not account for the length of the grass or the roughness or softness of the surface. 15% will be fine when the grass is short and the ground is firm and smooth but may be insufficient if the grass is longer or the ground is softer or rougher. Using a soft-field technique rather than the chart’s indicated short-field technique (see Note 1 above) may also influence this distance.

All this said, the chart in the POH is our best place to start on any takeoff calculations. You just have to keep the conditions and notes in mind and know when they won’t account for your current situation. Have fun and stay safe!

Half Sized Blog Element (Single Author Style)

Half Sized Blog Element (Multi Author Style)

Tips to Help Streamline IFR Training

Performance in the Real World – Part 2

Tips to Help Streamline IFR Training

Performance in the Real World – Part 2

Full Sized Blog Element (Big Preview Pic)

Tips to Help Streamline IFR Training

Performance in the Real World – Part 2

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