Safe Landings - July 2013

It has been said that the only voluntary act in aviation is the decision to take-off. Every action after take-off involves the skillful management of risk, the enjoyment of flight and a continuous stream of decisions that result in a safe landing.

In 1974, NASA created the Aviation Safety Reporting System (ASRS) to allow aviation professionals to share experiences in a frank, non-punitive manner. The ASRS structure allows pilots and other aviation professionals to file an anonymous report of an incident, error or occurrence that the contributor feels might be of value to others. These reports are gathered, analyzed and data based by NASA experts and made available to all interested parties as a tool for creating pro-active aviation safety programs. Additionally, NASA distributes an electronic publication, CALLBACK, which contains selected, de-identified, reports on a free subscription basis. In Flight USA is proud to reprint selected reports, exerted from CALLBACK, for our readers to read, study, occasionally laugh at, and always learn from. Visit to learn how you can participate in the ASRS program.

RNAV Standard Terminal Arrival Route (STAR) Issues

According to the Aeronautical Information Manual (AIM) Chapter 5, Section 4 (Arrival Procedures), a STAR is an ATC coded IFR arrival route established for application to arriving IFR aircraft destined for certain airports. RNAV STAR/Flight Management System Procedures (FMSP) for arrivals serve the same purpose but are only used by aircraft equipped with FMS or GPS. The purpose of both is to simplify clearance delivery procedures and facilitate transition between en route and instrument approach procedures. A link to the full text of AIM Section 4 can be found at the end of this CALLBACK. ASRS receives a significant number of reports every month related to difficulties with RNAV arrival procedures. Examples of reported issues include:
•    Complexity of RNAV Optimized Profile Descents (OPDs)
•    Flight crew workload
•    Aircraft system compatibility or capability
•    ATC familiarity with aircraft performance and requirements
•    Procedure interruption and phraseology

The following ASRS report excerpts provide insight into some of the complexities surrounding RNAV arrival procedures and in particular, the problems associated with the “descend via” clearance.


After having been cleared to “descend via” the GIBBS1 Arrival, the flight crew of an ERJ-170 was vectored off the arrival and uncertain as to their cleared altitude. Difficulty communicating with the busy controller to clarify the altitude forced a level off at an intermediate altitude until a new clearance could be provided.

• We were descending on the GIBBS1 RNAV into IAD between BBONE and KILMR when ATC assigned us a 020 heading for traffic. Our descent clearance was “descend via the GIBBS arrival” with no specific altitude given. I told my first officer to ask ATC what altitude he wanted us at and we got no reply. After two more unsuccessful tries to get an answer (the controller was busy), I leveled the aircraft at 11,000 feet, which was the altitude for the next fix. We finally got a reply to our questions and were told to continue to descend to 6,000 feet. ??As we had been cleared to “descend via” the STAR and, when vectored off of it, were no longer on the arrival, we had no guidance as to our cleared altitude. I’ve had this happen a couple times, with different altitudes given each time; some the same as the bottom altitude [on the STAR], some different. Anytime an aircraft has been given a “descend via” clearance and is later turned off the arrival, ATC needs to assign an altitude.


The Flight Crew of a CRJ-200, cleared to “descend via” the TRUPS1 Arrival, was understandably confused when given a heading change and then told to “continue” the arrival. The First Officer was the Pilot Flying and provides the first report on the incident.

• We were cleared to “descend via” the TRUPS1 Arrival and a second controller had cleared us to continue the arrival via the Runway 19 transition. Prior to reaching FRDMM waypoint, the controller told us to depart FRDMM heading 120, which seemed excessive. The [crossing] restriction at FRDMM is 8,000 feet. The pilot not flying queried the controller regarding the heading, but due to congestion he couldn’t get a word in edgewise. Finally, the controller issued new instructions to continue on the arrival. We were now at 8,000 feet and were past FRDMM [and were descending to comply with] the next crossing restriction of 6,000 feet [at STAND]. Shortly thereafter, the controller issued another heading change and took us off the arrival. Seconds prior, when [we were] on the arrival, we had continued our descent. I asked the captain to ask for clarification the controller replied that we were told to “continue on” the arrival and not to “descend via” the arrival. We quickly returned to 8,000 feet and were cleared for the River Visual shortly thereafter. The instructions were confusing at best. We were given a heading and, when we asked to confirm the heading, the response was changed to “stay on the arrival.” If the controller had said, “Stay on the arrival; maintain 8,000” the confusion would not have occurred.

From the captain’s report on the same incident:

• After crossing FRDMM, we started to descend to 6,000 feet per the STAR and at the same time the controller issued a heading change. I asked the First Officer if we should continue the descent since ATC just took us off the arrival and shortly after ATC asked us if we were still at 8,000 feet. I told him we were returning to 8,000 feet but thought we were still cleared to descend [as previously cleared] “via” the arrival. He explained that our new instructions were to “continue,” not to “descend via” the arrival.


A controller report highlights the confusion that can occur when runway “transition” clearances are given in conjunction with RNAV arrivals.

• It was a busy arrival push into PHX this morning. With the GEELA4 RNAV arrival there are quite a few more transmissions that need to be made to ensure the pilot will do what we need him to do. If the pilot is to “descend via” the arrival, well that’s a straight-forward clearance. When we have to vector the aircraft for sequencing, the phraseology to put the aircraft back on the arrival is very confusing. An A320 was issued a clearance to cross GEELA at and maintain 12,000 feet and 250 knots. The pilot read this back correctly. The pilot was then issued, “Cleared for the GEELA4 Arrival, Runway 7R transition.” At no point was a “descend via” clearance given or read back. The aircraft then called PHX Approach and said he was descending “via” the arrival. ??We need to come up with some type of phraseology that will allow us to clear the aircraft for the arrival and transition without the pilot thinking he is cleared to “descend via” the arrival. It seems the pilots are associating the runway transition with a “descend via” clearance. Maybe we should give the runway transition on initial check in, if that is legal.

The complete AIM Section 4 Arrival Procedures can be found at: http:// atpubs/aim/aim0504.html


Safe Landings - June 2013

It has been said that the only voluntary act in aviation is the decision to take-off. Every action after take-off involves the skillful management of risk, the enjoyment of flight and a continuous stream of decisions that result in a safe landing.

In 1974, NASA created the Aviation Safety Reporting System (ASRS) to allow aviation professionals to share experiences in a frank, non-punitive manner. The ASRS structure allows pilots and other aviation professionals to file an anonymous report of an incident, error or occurrence that the contributor feels might be of value to others. These reports are gathered, analyzed and data based by NASA experts and made available to all interested parties as a tool for creating pro-active aviation safety programs. Additionally, NASA distributes an electronic publication, CALLBACK, which contains selected, de-identified, reports on a free subscription basis. In Flight USA is proud to reprint selected reports, exerted from CALLBACK, for our readers to read, study, occasionally laugh at, and always learn from. Visit to learn how you can participate in the ASRS program.

Weather and Aeronautical Information Services and Data Link Issues

In cooperation with the Federal Aviation Administration (FAA), the Aviation Safety Reporting System (ASRS) initiated a study of meteorological (MET) and aeronautical information services (AIS) received via data link. The purpose of the study was to analyze information from users of data link technologies as reported in ASRS incident reports. Qualitative assessments of available records provided valuable insight on data link user interface and actual cockpit experiences related to data link weather or AIS information. The preliminary findings in the Study included:

The incident reports within the study group were almost equally divided between air carrier operations and general aviation

The majority of reporters’ comments regarding MET data link usage were positive and indicated that the technology was a valued tool in the mitigation of adverse weather encounters
The problems most often cited in regard to MET data link information were related to the timeliness of the data

The following ASRS report excerpts were taken from the data set that was used for the Meteorological and Aeronautical Information Services Data Link Study.

A Dangerous Dilemma

A PA-32 Pilot experienced hazardous weather conditions after relying upon data link weather for a “real time” picture of enroute conditions.

• While in cruise flight, it became necessary to deviate due to existing and building thunderstorms. ATC had advised me of the largest storm which I had visually… The storm was to the north. I was also using XM downloaded weather for information. When the XM indicated it was safe to turn more northerly, I advised ATC that I was starting my turn and he agreed that the turn looked “good to him.” I went IMC momentarily and when I broke out there was a large buildup at my twelve o’clock position. The main storm was still off to my right. I could see several breaks around the buildup. I requested and was approved for a climb to 10,000 feet in an attempt to remain visual on the buildup. I was unable to do so and encountered IMC. While IMC, I flew into an area of fast building weather that was joining up with the known cell to my right. I advised ATC of my dilemma and he was very surprised to see how quickly the cell was developing. He vectored me through the safest part of it. I was forced to use every method from my training by turning the autopilot off, slowing, and keeping the wings level. At one time with [climb power] I was descending at 1,500 feet per minute. I eventually exited the weather…. ATC advised that the area had completely closed up. Only then did the XM weather update to reflect the actual conditions that existed. The great guy at ATC was almost as nervous as I was. The delay of the update with the speed of the buildup of these air mass thunderstorms resulted in an inaccurate pictorial that I was using to determine my route of flight.

“I Thought I Would Have an Uneventful Arrival”

When fast moving convective activity is present, more than a good preflight briefing and onboard NEXRAD information may be needed to keep up with current conditions. After enduring an unexpected “flight” on the ramp, this M-20 Pilot recognized that a false sense of security was a factor in his not getting real time data from Flight Watch.

• Just prior to departure I received a full VFR weather briefing which contained no SIGMETs. The forecast was VMC for the entire route. Mention was made of some convective activity, but it was not expected to affect my route of flight. Enroute, I had access to XM weather and SkyRadar. One hour prior to my ETA, I noticed a large cell with Level 6 activity within… I made some preliminary plans for an alternate, but as I approached within 20 minutes of my destination, I thought I would have an uneventful arrival. ATIS was reporting winds 280 degrees at 10 knots gusting to 14 knots with a broken ceiling at 5,500 feet. Approach Control and Tower casually mentioned the weather, but there was no sense of urgency concerning the developing situation. On a two mile final, lightning struck the field. As I flared to land, a large microburst was observed on the airport and wind gusted to 40 knots. By this point I landed and started to taxi to the ramp. Rain and wind became torrential and the aircraft started to weather vane on the taxiway. I maintained appropriate control inputs and made it to the ramp where I turned the aircraft into the wind, kept the engine running and maintained full forward yoke and full nose down trim. At times the wind gusted to 55 knots. The NEXRAD display was displaying Level 6 returns over the field. The rainwater on the ramp had whitecaps. Tower did a great job of keeping me informed of wind direction and speed. I “flew” on the ramp for 20 minutes before the winds let up…. I have always considered myself cautious and not a risk taker. I have not hesitated to deviate in the past when weather was dangerous. I am ashamed of my judgment during the conclusion of this flight. There were several factors that led to my decision… I had a false sense of security about the weather that led me to make an inappropriate decision. I could not believe a convective cell could move that fast… I should have been talking to Flight Watch to get real time data about the direction and velocity of the cell.

TFR Troubles

The ASRS Data Link Study noted that a number of incident reports cited missing, inadequate or late AIS data. This PA-28 Pilot’s experience was an example of how delayed TFR information can “pop up,” after it is too late.

• I departed…and flew direct…on a VFR flight. I thought I was departing just prior to the Presidential TFR, which I believed to be starting in 15 minutes… Unfortunately I was mistaken on the TFR start time either due to a change or an error on my part, but the TFR went into effect two minutes before I departed. I was asked upon landing to call the FAA, which I did…. The AWOS that I checked via phone prior to departure did not have any special NOTAMs for the TFR… In addition, my Garmin 496 must have been delayed with the data feed because I only saw the TFR pop up on my display as I was leaving the TFR.


Safe Landings - May 2013

Gear Up Landings – Getting a Handle on the Problem

Over the past five years, ASRS has received an average of 60 gear up landing reports per year. Gear up landings rarely meet the damage or injury requirements for a National Transportation Safety Board (NTSB) report or investigation and they are seldom reflected in general aviation safety statistics. Nevertheless, no pilot wants to experience a gear up landing. There is always the potential for a serious outcome and the repair costs associated with any gear up landing can be substantial. 

To avoid the risks and costs associated with gear up landings, pilots can get a handle on the lessons offered in these ASRS reports.

Scrape and Go Landing

A malfunctioning gauge, failure to use a checklist and the absence of a gear warning horn were all factors in this blade-bending low approach.

• A Student Pilot and I were performing practice landings in a C172RG. On the upwind of a touch and go we noticed that the manifold pressure gauge was reading atmospheric pressure no matter what the throttle position. The engine was still performing normally, but we decided to make the next landing a full stop. I took the controls momentarily on the start of the downwind so that the student could tap the gauge. We exchanged controls again and requested a full stop. We were performing short approaches and got clearance for another short approach. The Student reduced throttle (the manifold gauge still read atmospheric pressure) and selected flaps to 20 degrees. We touched down gear up, the Student added power and I took the controls and put the gear down. 

As I climbed out, an aircraft in the run-up area notified Tower about what had just occurred. Tower asked if we needed any assistance. The plane was flying normally so we declined, obtained a clearance to land and flew the pattern. I flew the aircraft, performed a soft field landing and taxied back. Upon shut down it was found that the prop did strike the ground. 

There were several human factors involved…. I failed to verify that the gear was down with my own checklist. I also relied on the aircraft too much to warn us that the gear was not down, but due to the fact that the manifold pressure was at an atmospheric level and the flaps were only at 20 the horn did not go off. 

The cause of the prop strike was lack of checklist usage, lack of communication during the exchange of controls, fixation on the inoperative instrument, complacency, and failure to verify that the gear was down…. Also, we should have notified Tower of the manifold pressure situation. It might have slowed us down in the cockpit as well as drawn attention to us by the Tower who may have notified us that our gear was still up. 

A Hull of a Mess

Switching from wheels up for water landings to wheels down for hard surface landings requires an extra measure of attention for pilots of amphibian aircraft. A series of water landings followed by distractions on final contributed to this Amphibian Pilot’s off-lake, gear up landing.

• I was supposed to have a Biennial Flight Review (BFR) and insurance re-currency flight in an aircraft that was right out of annual inspection…. I had not flown in 12 months so I was rusty and my Instructor was aware of this. We got in the air and did some pattern work. After about six landings we departed the airport to do some water landings and taxi work…. I proceeded back to our departure airport and was given a straight in approach for the runway. I was distracted with a logbook issue along with the fact that I would not be able to get my plane back to its base because I was not night current. We got into a conversation on how to proceed while I was on short final. We were both distracted and not going through the checklist and landed on the hull, gear up. 

I know that I share some blame on this because I know better than to be distracted in the cockpit.

If at First You Do Succeed…

It is never a good idea to second guess a landing gear warning indication. You might get away with it once or twice, but as this Bonanza 36 Pilot learned, there are times when it is not prudent to try, try again.


• The aircraft had been sitting in the owner’s hangar for several months without activity and I had been asked to fly it. The records available and the preflight all seemed excellent and all went well until I was to land. I did not get the gear down indication. I asked the Tower to visually check my gear and they suggested a low pass…. As I turned crosswind I could see my shadow on the ground and I could see that the gear was indeed down. As I passed the Tower I did not get a transmission from them. I proceeded to land as previously instructed and noticed that the radios were failing which explained why I had not heard from the Tower. I landed without incident and followed an operations vehicle to the main ramp and my hangar.

I discovered that the problem was loss of battery power and alternator output…. The electrical problem was corrected during the evening by re-charging the battery. I felt this had explained the gear indication problem and the radio failures.

On the following day… the Before Start and Taxi Checklists were completed and it was noted that all systems were functioning and three green lights with gear down were noted. Subsequently the flight proceeded to a nearby airport. I planned to use this uncontrolled field to do several takeoffs and landings to become familiar and current in the aircraft.

On the first landing I did not see three green gear lights, but there was no gear warning horn. Based on having had this same scenario the day prior, I continued and landed without incident. Because of a change in winds I decided to switch runways for the next takeoff and landing. This was accomplished with the same experience of no green gear down lights, but also no gear up horn.

Becoming uncomfortable with this condition, I decided to return to my final destination for resolution of the discrepancy. 

I was cleared to enter a visual right base…. When I put the gear down I heard no gear horn, but I did not see three green lights. The aircraft settled to the runway level and slid straight ahead. The gear were actually partially extended, but apparently not locked. I immediately exited the aircraft having shut the fuel off, closed the mixture and turned off the battery, alternator, and ignition. There was no fire or smoke, and I stood on the runway awaiting assistance.

Before flying an aircraft that had been so long in storage, maintenance personnel should have been consulted and an inspection and survey of the aircraft for proper airworthiness should have been made. My unfamiliarity with the aircraft was certainly a factor also.


What Goes Up, Doesn’t 
Always Come Down

Troubleshooting an electrical problem, a C210 Pilot, accompanied by a Maintenance Technician, cycled the landing gear a few times and then lowered and verified the gear down for a final landing. In an effort to make one last check, the gear was cycled again. Unfortunately, only half of the cycle was completed.


• The aircraft had just come out of repair for a failed alternator. Upon starting the engine the alternator again failed, but after shut down and restart, it worked until just after takeoff then failed again. So I landed uneventfully and returned to the FBO. During taxi the alternator restarted then briefly failed again. The Mechanic offered to come with me for a test flight to see if an over-voltage transient could be triggering the problem. At his suggestion, we stayed in the traffic pattern, cycling the gear up and down a few times, but could not duplicate the problem. After the first touch and go we still hadn’t seen a problem. On downwind, I lowered the gear as usual and did a GUMPS* check. The Mechanic then suggested cycling the gear once more. I raised it, but failed to lower it. Just before touchdown, the Tower noticed the lack of gear and called for a go-around, but it was too late and we landed gear up with full power.

Lessons: 1) Do maintenance work at altitude away from the airport 2) Maintain a sterile cockpit in the pattern and, 3) Do a GUMPS check on final.


*GUMPS is a commonly used acronym that is used as a final check to ensure that an aircraft is properly set up for landing. It should not be used as a substitute for the specific aircraft’s descent, approach, and landing checklists.

Gas (fullest tank)

Undercarriage (gear down and locked)

Mixture (full rich)

Propeller (high RPM)

Switches (fuel pumps, magneto check, landing lights, etc.)

C-GUMPS can be used when flying a plane with a carbureted engine; “C” standing for Carburetor (heat on).



Safe Landings - April 2013

It has been said that the only voluntary act in aviation is the decision to take-off. Every action after take-off involves the skillful management of risk, the enjoyment of flight and a continuous stream of decisions that result in a safe landing.

In 1974, NASA created the Aviation Safety Reporting System (ASRS) to allow aviation professionals to share experiences in a frank, non-punitive manner. The ASRS structure allows pilots and other aviation professionals to file an anonymous report of an incident, error or occurrence that the contributor feels might be of value to others. These reports are gathered, analyzed and data based by NASA experts and made available to all interested parties as a tool for creating pro-active aviation safety programs. Additionally, NASA distributes an electronic publication, CALLBACK, which contains selected, de-identified, reports on a free subscription basis. In Flight USA is proud to reprint selected reports, exerted from CALLBACK, for our readers to read, study, occasionally laugh at, and always learn from. Visit to learn how you can participate in the ASRS program.

Rotorcraft Roundup

We’ve corralled a few helicopter reports since the last “Roundup” and present them here for the benefit of all hands. While helicopters and fixed wing aircraft may differ in form and function, most of the basic principles of safe operation apply to both. So, no matter what sort of rig you’re riding, everyone in the outfit should be able to wrangle a lesson or two from this roundup of ASRS helicopter reports.

Put Your Boots on Before You Saddle Up

Distractions, including a lack of boots, caused this MD-500 Pilot to forget a critical item in gettin’ the rig ready.

• At the beginning of the shift, I performed the pre-flight inspection of the aircraft and noted that the fuel level was down below 300 pounds and was going to need to be topped off. Normally when an aircraft is left down for fuel, the crew leaving it down is supposed to leave a placard on the instrument panel alerting other crews of the fuel situation. In this case there was no placard left on the panel. Due to the hot weather, I performed the pre-flight inspection in my civilian clothes (shorts and T-shirt). Once I pushed the aircraft out of the hangar, I decided it would be better to fuel the aircraft once I had my flight suit and boots on, in case fuel was spilled while fueling. I left the aircraft without a placard on the panel and went inside to change my clothes.

Once I changed into my flight suit, I was distracted by administrative details inside the office and forgot to go back out and fuel the aircraft. Approximately one hour later, we took off on a mission and I failed to note the reduced fuel state. I believed that I had a full tank of fuel and I was only planning on flying for one hour. A full tank of fuel will normally allow two hours of flight time with a reserve. About an hour into the flight I noticed a yellow caution light briefly flicker. I pressed the “Test” button and realized the light was the “Low Fuel” caution light. It was indicating below 100 pounds of fuel. Realizing that I had forgotten to fuel the aircraft prior to departure, I turned toward the airport and reduced power, but then I decided to make a precautionary landing in a suitable area rather than risk having a flameout trying to make it back.
Upon noting the low fuel state during pre-flight, I should have immediately put fuel in the aircraft so that it was mission ready. To alleviate this situation in the future, I should always pre-flight the aircraft in the proper clothing so if the aircraft needs to be serviced I will be able to take care of the situation immediately. Another option is I could have left a placard on the panel upon noticing the low fuel state, which would have reminded me prior to takeoff that the fuel level was low.

Clouds Along the Trail

Stumblin’ into IMC is often cited as a factor in weather related incidents and accidents. Getting a thorough pre-flight weather briefing along with making contingency plans can go a long way toward easin’ the effects of weather. This helicopter wrangler learned just how quickly a change in the weather can result in a change of plans.

• The weather [was] clear; visibility 10 miles…Enroute I noted a broken ceiling at 900-1,000 feet. [At] 1,500 feet I noted extensive cloud/fog cover below on the route of flight [and] I was unable to maintain visual contact with the ground. [I] elected to return to the point of departure.

Deteriorating conditions were encountered about 40 minutes from the departure airport. I checked weather at [a nearby airport] which showed broken at 1,200 feet. Upon arrival, however, conditions were solid overcast and deteriorating. After conversing with the Tower, I elected to declare an emergency due to my fuel state and the need to descend through the clouds. The helicopter is not IFR equipped and I am not instrument rated. I descended through the clouds, breaking out at about 1,000 feet AGL and landed without further incident.

A TRACON Controller gave the ATC perspective on the same incident.

• The airport was reporting a marginal VFR ceiling of 1,000 feet overcast. A helicopter called about 25 miles West of the airport inbound with the ATIS. I vectored him for sequence and…then told him to resume his own navigation to the airport. I called him three times, giving him the location of the airport. He did not answer until the third call and he said that he couldn’t see the airport because there were some clouds between him and the airport. I told him to maintain VFR and contact the Tower. A couple of minutes later, the Tower called me and advised that the aircraft was an emergency with low fuel and unable to get down. I checked with three other aircraft in my airspace looking for a hole in the clouds, but none were found. The crash crew responded and other traffic was broken off of the approach behind him as he maneuvered down through the clouds.

I had worked the helicopter for about 25 miles. He said that he had the ATIS with the reported overcast layer. He accepted traffic calls and said he was looking for traffic. At no point did he indicate any fuel criticality nor did he mention that he might have any issue descending. Only once did he mention clouds between him and the airport. I assumed this was a small scud deck that he expected not to be an issue. The pilot should have mentioned his concern with the weather much earlier. It goes without saying that the pilot should have checked the weather before getting airborne and taken on sufficient fuel.

A Wild Ride

Two fella’s hitched up an R22, wandered into some weather, went for a wild ride and wound up headin’ straight for the ground. Luckily they were able to rein in their helo and set ‘er down in a pasture.

• My student and I departed…on a cross country flight under VFR conditions…after the fog had cleared. The clouds were high and we could see for miles on end. We flew GPS direct…and [then] the clouds got lower, going from 1,000 feet to 600 feet AGL. There was also some fog near the ground that was thinning. We decided to proceed North…around protected airspace…and then head West towards [an] airport which was reporting better weather. We were able to maintain VFR cloud separation at 300 feet AGL until we reached the northern tip of the protected airspace where we hit some low, dense fog.

Knowing that there was better weather nearby, my student and I continued onward, flying a gradual descent to stay clear of the clouds. We reached a point at about 200 feet AGL where we could no longer fly any lower due to the terrain and tall trees and decided to turn around and abandon our cross country. As we began the turn, we entered the clouds and inadvertently went into IMC. Since we couldn’t see any obstructions around us we decided to also climb back up to 400 feet AGL to avoid hitting anything in the turn. We then became disoriented and soon afterwards we came out of the clouds with the nose pointed straight down. I recovered from the pushover and landed in a field nearby to assess any damage to the helicopter. Upon finding no appreciable damage, we flew the helicopter directly back to [our home field].

In hindsight we should have abandoned the cross country sooner instead of pushing on into the clouds. Had we decided to land at the intermediate airport or turn around to go back home, we wouldn’t have entered the clouds and become disoriented.


Safe Landings - March 2013

You and UAS

Unmanned Aircraft Systems (UAS) — also referred to as “Unmanned Aerial Vehicles” (UAV’s), “Remotely Piloted Vehicles” (RPV’s), “unmanned aircraft” or “drones” — come in a wide range of configurations and sizes, and have multiple military and civilian functions.

UAS operations utilize a Pilot-in-Command who is controlling the aircraft from a remote location. In the event of a data link failure or other malfunction the system may revert to a pre-programmed mode.

The FAA is under congressional mandate to integrate most UAS into the National Airspace System (NAS) by 2015 (2014 for UAS weighing less than 55 pounds) with the primary focus and authority being safety. In planning the integration of UAS into the NAS, the FAA has to develop a safe and efficient way that these systems can operate in the same airspace as crewed aircraft without creating a hazard to other aircraft or to people and property on the ground.

To date, UAS access to the NAS remains restricted pending development of appropriate operational procedures, standards, and policies. The FAA approves UAS operations on a case-by-case basis. UAS authorized by the FAA to operate in controlled airspace have to comply with appropriate FAR or equivalent military standards related to aircraft and operator certification as well as equipment and communication requirements.

The following ASRS reports are presented to increase Pilot and Controller awareness of UAS operations and to provide some insight into the systems from an Operator’s viewpoint. Additionally, UAS Operators may gain a better appreciation of the interaction of UAS with other elements in the NAS.

UAS Altitude Excursions

Four ASRS reports describe incidents in which UAS departed from their assigned altitude. In the first report, an Air Traffic Controller observed a UAS altitude deviation and also expressed concern for the consequences of UAS data link failures.

• While working an adjacent sector, I witnessed a UAS deviate from his assigned altitude. This UAS was cleared to maintain FL350. The [UAS] aircraft descended out of FL350 to FL300 without a clearance. When questioned by the Air Traffic Controller, the Remote Pilot stated that he could not maintain FL350 so he descended. 

I feel this event happened due to the training of the Remote Pilots of the unmanned aircraft. The accountability and standards for remotely piloted, unmanned aircraft should be equal to the standards of commercial pilots. 

Also, unmanned aircraft must be held to the same restrictions as manned aircraft. For example, in a [UA] System, if the aircraft loses data link it will fly its programmed flight plan. It will not maintain its last assigned altitude. This can affect the Controller’s ability to maintain positive separation.

An Operator reported losing aerodynamic control of the UAS and was too busy reestablishing control to immediately notify ATC of the problem. It is not known if the UAS Copilot had communications capability with ATC.

• I requested a climb from FL190 to FL250 to climb above weather. Before entering into a climb, I asked the Copilot to perform a full sweep with the camera to look for clouds and adverse weather. None was noted. 

Climbing through FL210, conditions were encountered that affected the performance of the [UAS] aircraft and resulted in a loss of altitude from FL210 to 16,500 feet MSL. Due to my efforts to fully regain positive control of the aircraft, I failed to declare an emergency. As soon as I regained positive control, I initiated an immediate climb to the cleared altitude of FL250. ATC advised of the deviation in altitude. I advised ATC that the descent was due to weather and the aircraft was currently in a climb to FL250. The flight level request was amended to FL290 in order to fly above the weather.

A Certificate of Authorization (COA) from the FAA authorizes a UAS operator to use a defined airspace and includes special provisions unique to each operation. Most, if not all, COAs require coordination with an appropriate Air Traffic Control facility and may require the UAS to have a transponder to operate in certain types of airspace. The UAS Operator who submitted this report to ASRS was operating in accordance with a COA when the data link to the UAS was lost.

• My UAV was conducting assigned missions at FL200 in accordance with a COA issued by the FAA. At one point in the mission the UAV descended to FL190 without an ATC clearance. At the time of this violation, we lost a control link…with the [UAS] aircraft. As we were then unable to verify the aircraft’s position or obtain critical flight information, the command link with the [UAS] aircraft was disabled releasing it on its emergency mission profile in accordance with the approved emergency checklist. The [UAS] aircraft then began squawking 7600 and entered autonomous flight proceeding direct to the assigned emergency mission loiter point and descended to a pre-programmed altitude of FL190. 

The remote command link with the UAV was lost for several minutes. This command link allows the aircraft to be flown by a PIC approximately 1,000 miles away using satellite relayed commands. It was this link that was lost and the aircraft was then released to its pre-programmed emergency rendezvous point where it would then be picked up visually and landed by on-site operators. In this case the command link was regained after several minutes and the aircraft flown directly by the PIC to a point where it could be visually acquired by the on-site crew and was landed safely. Maintenance investigation is required to ascertain the reason for the lost link before the aircraft is again released for flight operations.

In another report from a UAS Operator, the aircraft experienced an altitude and heading deviation due to loss of the data link, but the Operator made a timely report to ATC.

• Due to an inadvertent SPMA (Signal Processor Modem Assembly) reset during a backup communications power up, the UAS experienced a Lost Link situation. The UAS was cruising at FL230 to avoid weather when the Lost Link occurred. The Operator failed to update the Lost Link Profile to reflect the ATC clearance which caused the aircraft to turn towards the closest Lost Link entry point and initiate a descent to FL190 which was the previous Lost Link Profile. The Operator immediately called ATC and notified Center that the link should be regained within two minutes. Once the SPMA link was reestablished, the aircraft climbed to its previous altitude of FL230. 

No additional information was requested by Center after communications were regained and the flight continued without further incident. A software change request is being researched for added protection from inadvertent SPMA resets.

Close Encounter

A small UAS encountered by the Pilot of a manned aircraft may have been outside its designated airspace. If ATC is not aware of a UAS, Pilots have to rely on see and avoid procedures and handle UAS conflicts the same as conflicts with manned aircraft.

• My passengers and I noticed an oblong shaped UAV (approximately two to three feet long with a long antenna) passing us in the opposite direction within 100 feet of our left wing on the 45-degree entry to Runway 15…. The object did not show up on my TCAS system as a threat. These vehicles need to show up in the cockpit as a threat or stay within the Military Operating Area (MOA).

Additional UAS information can be found at the following FAA websites:


The Aircraft Owners and Pilots Association has a free interactive course, Unmanned Aircraft and the National Airspace System at:

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